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HELP LB7 no start for 13 weeks!!

17K views 43 replies 14 participants last post by  PewterLB7 
#1 ·
Problem:
2002 Chevrolet Silverado 2500HD with Duramax LB7; no start after installation of injectors rebuild, water pump, FPR, and other components.
Background:
This truck only has 100K miles. It has been taken care of and serviced impeccably and I do not abuse the truck. I did not take advantage of the extended injector warranty as there was no need at the time. Truck ran great and strong with exception of idle surge and slow leak in water pump. No fuel or coolant in the oil, no codes other than a code (can’t remember the number) that dealt with either the glow plugs or glow plug controller. The truck also had clean exhaust; no smoke. Okay, all of the above background was the situation before I began working on the truck.
Present Situation:
Okay, let me begin by stating that all of the components that I replaced (I will list them below) are OEM quality GM, Bosch, AC Delco, Delphi or Gates. Secondly, and I really hope this doesn’t come off as being arrogant but, I’m extremely careful, clean and meticulous (bordering on being obsessive compulsive). I’ve worked on all types of engines, hydraulic pumps, etc. I have to admit, I’ve never been this frustrated with a mechanical problem. One more thing; and I hope I don’t hurt anyone’s feelings, but please don’t ask me if I have fresh fuel in the tank or anything like that. I have been working on this problem for over thirteen weeks and have had the help of a retired Chevrolet gas and diesel mechanic. Lastly, if you really want to help, please carefully read the entire post (novel, ha, ha) so you don’t waste your time or my time on issues that have already been addressed.
Work Done:
Before starting work I carefully cleaned the engine by applying degreaser and light pressure washing, being careful to stay away from the FICM and other electronics. It was actually pretty clean before I started and was dirt and grease free when I finished. I also took pictures of wiring routing, hose positioning and any other items that could possibly create confusion on reassembly.
  • Installed a new AC Delco water pump and housing. I had the impeller and drive gear carefully welded to the shaft. Of course, used all new “O” rings and gaskets on pump and bypass pipe.
  • Installed all new coolant hoses (Gates), steel idlers (Gates), thermostats (AC Delco), coolant reservoir cap and HD serpentine belt.
  • Installed a new Bosch FPR. Prior to taking the old one out I sprayed the rear of the CP3 pump with carb cleaner and blew it dry with compressed air. After the old FPR was removed I took great care not to “cock” the new FPR on installation as well as very lightly coating the “O” ring with clean diesel fuel before insertion. I made 4 passes of tightening the 3 screws on the FPR so it would go in straight and then reattached the connector.
  • Installed all new OEM low pressure fuel hoses. Secured the hoses using 2 worm gear clamps positioned 180 degrees apart on each end. I had taken pictures of the positioning of these hoses as well as removing and installing the new ones, one at a time so they couldn’t be connected wrong.
  • Installed a new quality fuel filter. Rebuilt the priming pump on the fuel filter housing and installed a brass bleeding bolt. After pumping up the primer I checked for leaks around the top of the filter where it meets the filter housing with the big “O” ring, as well as the WIF, bleeder screw and fuel heater connection hole, all were bone dry, no leaks.
  • Next came the injector nozzle replacement. Before I began, I sprayed carb cleaner around the valve covers where they would be removed and then blew everything out with compressed air a second time to make the area “squeaky clean”. During disassembly I laid everything I took off on my workbench so I would keep them in order and additionally numbered the injectors to keep them also in order. I won’t bore you with additional detail of how clean and meticulous I tried to be with the nozzle replacement (they were standard Bosch nozzles for my type of injectors). After sonic cleaning the various injector parts, I blew all orifices out with carb cleaner, then compressed air and finally WD40 to keep everything lubricated. While I was doing the nozzles I went ahead and invested in an injector upgrade kit (OEM parts) which included the improved valve seat ball, new springs, etc. for all 8 injectors. I also ohmed-out all 8 injector solenoids and found them to be fine. The injectors (other than the nozzles which were only moderately carboned-up) were surprisingly clean. I also checked, as well as I could with a magnifying glass, the valve seats which looked great with no apparent erosion. I got the injector rebuild kit with the valve cover gaskets, metal banjo gaskets for the high pressure lines, etc. I made sure to install the metal banjo gaskets right side up to avoid leaks and torqued everything down according to specs. I did decide to use the original injector high pressure lines because they were in such good shape. There was some rust on the lines where they connected to the inside section of pipe that enters into the valve cover, but absolutely no rust on any of the connecting mating surfaces. I took all eight injector lines and submerged the ends in navel jelly for about 5 minutes; they were then rinsed thoroughly, then sonic cleaned and once again blown out with carb cleaner and compressed air and finally lubricated with WD40.
  • Installed 8 new U.S. made glow plugs with metal connecting straps. Old glow plugs came out fine with no damage to threads. Cleaned all wiring connections of any corrosion before reassembly.
  • Installed a new glow plug controller (Delphi) and, once again, cleaned all cables and connectors of any corrosion.
  • Just in case, I replaced my fuel cap with the correct GM OEM part to assure proper pressure/suction on the tank.

First Attempt to Start Engine:


  • After refilling the cooling system (the complete system was drained) with the proper coolant. I then double-checked all electrical connections, charged the batteries and checked for codes. I came up with 0090 and 0193. This indicated an issue with the FPR and/or FRPS. Took the A/C compressor and other components back off where I could get to the FPR again. I unlatched the two large connectors and found the FPR purple/white stripe wire (from the wiring diagram) and corresponding pin on the large connector. Turned on the ignition and did a continuity test coming out of the ECM to the pin on the male section of the connector; I had voltage to that point. Then I needed to check continuity from the female section of the large connector back to the FPR. I was able to carefully remove the connector on the FPR with the help of some long curved needle-nose pliers and a long thin screwdriver to lift the latch. When I got it out to test I noticed the connector was cracked. Just to be sure I checked for continuity and that test failed. Ordered a new FPR connector with 6 inch leads and silver soldered the leads to the existing wiring to the FPR after cutting off the old connector and used shrink tubing on the repairs. Note that I made certain to match up the correct orientation for the two wires to make sure I did not reverse them. Ran the continuity test again at the connector, and had good voltage. Just as a test, I took the old FPR and attached it to the repaired connector and turned on the ignition; the FPR solenoid clicked on properly. Took the old one off and carefully reattached the connector securely to the new FPR and buttoned everything back up. Ran my scanner again; deleted the previous codes and re-scanned. Came up with zero codes. Ran it a second time just to be sure.
  • Okay, when I ordered the connector for the FPR, I also ordered a new Bosch FRPS as well. Even though the 0193 code went away when the FPR connector was repaired, I went ahead anyway and replaced the existing FRPS and metal shim with a new one. Once again, there were zero codes. One thing that I did notice when I unscrewed the old FRPS, is that the high pressure junction box that I removed it from, had no diesel fuel in it.
Second Attempt to Start Engine:

  • Charged batteries again and rechecked all that I had done since last attempt. Ran scan a third time; no codes. Primed fuel-filter ten pumps or so and opened up bleeder; continued pumping until nothing but steady fuel was coming out. Closed bleeder and pumped 25 to 27 times and got the pump rock-hard. Went in and turned the engine over for ten seconds or so, three times. No start. Went back and repeated above steps again. Went in and tried again in the same way; no start, not even a “kick”. I repeated the above scenario another four or five times until the batteries were drained; no start.
  • Charged batteries and the next day I repeated everything over again until batteries, once again, were dead.
Third Attempt to Start Engine:
At this juncture I got on line again and started reading anything and everything about a “no-start” LB7 and did the following.

  • Checked fuel filter housing for leaks or cracks. Pumped up primer until plunger was rock-hard; sprayed soapy water all over fuel filter and looked for leaks. No leaks found. Note that I checked for bubbles while pumping up the primer as well as when it was rock-hard.
  • Pumped up primer again until hard and looked for any leaks in high or low pressure fuel lines. No apparent leaks, no smell of diesel fuel; everything bone dry. Even checked fuel lines back to tank; no leaks, everything dry.
  • Crawled under truck and checked the CKP (crankshaft position sensor). Unconnected connector and checked for loose fit, corrosion or bent pins. Everything fine, reset connector into sensor.
  • Crawled under truck and checked the CMP (camshaft position sensor). Unconnected connector and checked for loose fit, corrosion or bent pins. Everything fine, reset connector into sensor.
  • Checked all connectors for bent pins, corrosion and loose fit on FICM and all other connectors that I could get to. All of these connections proved to be fine.
  • I checked the “O” rings in the fuel line quick connects. Both lines were bone dry at the connections. By the way, when I originally disconnected them to replace the driver side injectors, I cleaned the lines at the quick connections really good with compressed air then sprayed up into the connectors with silicon lubricant so that the “O” rings would have an easier time sliding off the end of the steel lines as well as when they were to be re-attached to the steel lines later.
  • I double-checked the rubber hoses between the engine's quick connect fitting and the CP3's inlet fitting. Once again, all low pressure fuel lines were replaced with new OEM hoses and the clamps were tight.
Did all of the above and tried again to start engine after charging batteries up. No start!
Additional Attempts to Start Engine:

  • This time I went through the exercise of priming, bleeding and re-priming until the primer was rock-hard and I continued to pump the primer as a helper turned over the engine. Did this exercise many times until the batteries died; no start!
  • Another attempt had me having a helper pressurize the fuel tank with 3 to 5 psi pressure by wrapping a shop towel around an air hose and holding it tight in the fuel pipe. I then went through the priming exercise again doing this procedure three times; no start, not even a “kick”. Then I did it again with the above helper pressurizing the tank and another helper (wife) turning on the ignition as I continued to pump the primer as we turned over the engine. No start!
  • At this point I brought in a friend who retired from our local Chevrolet dealership with nearly 30 years-experience in gas and diesel repair. He now has his own shop. He brought over the same testing equipment that they use at the dealerships. I had the batteries charged for him and he proceeded to run his diagnostic equipment. He concurred with my diagnosis and also came up with zero codes and said that there were other tests that he would like to run, but they had to be done with the engine running. However, he went on to say that with what he could see so far we should be able to at least start the engine. We took some time to go over what I had done and he visually inspected my work. He then asked if he could do the priming himself as I turned over the engine. We did that numerous times until we depleted the batteries again. He did mention that his experiences with the Duramax engines had shown some to be especially stubborn to free all of the lines and fuel rails from air regardless of the methods used. He also mentioned that many of the no starts that came into the dealership was a result of deterioration of two flex areas in the supply fuel line coming from the tank. The first rubber hose flex section is in the engine bay on the driver’s side as the metal fuel lines come up beside the firewall. The second area is under the truck on the driver’s side roughly under the driver’s seat. These rubber sections are incorporated into the fuel lines to provide flex for the engine and any flex in the body and frame. They are installed on the larger supply line as well as the smaller return line. The problem is, after time they begin to deteriorate and soften and when suction is created (as in priming the fuel filter) they can collapse, squeeze together and prevent fuel flow. Okay, so we checked the flex fuel supply hose in the engine bay and he said it felt fine, however, when he crawled under the truck he had me squeeze the flex hose under the driver’s seat area and it was mushy. He told me how to fix it. They use a small Dremel tool to carefully cut off the crimped ends, being careful not to cut too deep and damage the steel fuel line underneath. After both ends are cut off and the old flex section is removed they install a section of premium HD hose with double hose clamps. He called the dealership and they had some in stock. It was heavy duty Parker hydraulic hose about 10 to 11 inches long. It took me about 45 minutes to do the whole job. I checked for leaks and recharged the batteries. My mechanic friend told me that he had six cars ahead of me, but wanted me to go ahead to see if I could get it started after I made the hose repair and that he would get back with me after he cleared out some of the cars he was working on. I, once again, went through the proper priming exercise and tried to start the engine, priming and turning over the engine 5 times. No-start!
Present Situation:
This brings us up to the present. I refuse to give up on this problem, but I am at a point where I feel like pulling what little hair I have out. I am running out of ideas and need help from someone smarter and more enlightened on this subject than me. My mechanic friend informed me that his daughter, who lives out-of-town, just had a baby and that it is probably going to be a while before he can get back with me. This whole ordeal has left me with some questions that I would really like answered; they are as follows:

  • The first question is, when I pump up the primer on the fuel filter and get it hard; is it supposed to remain hard over an extended period of time or is it natural for it to slowly lose pressure? The reason that I ask is that when I pump mine up and get it rock-hard it doesn’t take it long before I have to pump it up again to make it hard again. The information on-line has been contradictory; some sources say that even on an engine that runs and starts fine, the fuel primer will slowly lose pressure, other sources say no, the primer should continuously stay hard. Which is correct?
  • The next question is a big one for me because the answer to it is going to determine whether I have a lot more work in front of me or whether I can simply focus on getting the engine started. The question is this; do you think I have a faulty FPR? I have tried to learn everything I can about the FPR and its role in the fuel delivery system. As explained earlier, I replaced the original FPR with a new Bosch sealed box replacement. And as I confirmed earlier I know that I have power going to the FPR and I further know that when I repaired the FPR connector we eliminated the 0090 and 0193 codes. So my question is this, can the scanner show that there is no code for the FPR but still have that FPR be faulty; and how common would it be that I would receive a faulty FPR from Bosch? If I have to go in and replace it I have to drain the coolant and tear the top of the engine down again; I really don’t want to do that based simply on “maybe” the FPR was bad. Okay, here is the last question regarding the FPR. It seems to me to be another contradiction in regard to what I am learning on-line and in repair manuals. According to what I have learned, the FPR doesn’t really regulate fuel pressure; it controls the volume of fuel to the high-pressure side of the CP3 pump. Okay, if that is the case, does that mean that it is absolutely essential that the FPR be functioning properly for the engine to start or does it simply mean that the FPR is absolutely essential for the engine to run smoothly and efficiently after it is started? I have read some diesel blogs where they are saying how they disconnected the FPR then ran the engine to test for other issues. Are they saying that yes, the engine can be at least started without the FPR being energized? The reason that this question is so important to me is that if the FPR is not absolutely essential to start the engine, then I have to look elsewhere for the no-start problem.
  • Another question; or maybe this is simply a recommendation. Should I install a lift pump? Before you answer that question let me tell you what I need out of my truck. I will be using this truck pretty much for only one thing; pulling a car trailer for restored antique MGA sports cars (they are small). I belong to an MG club and we have meets all over the U.S. where we trailer in our cars. Just so you understand, I’m not pulling a huge fifth wheel travel trailer or anything really heavy, just a relatively lightweight trailer with a small sports car. Also, I’m not interested in modifying my engine to develop 700HP; what I am interested in is reliability and longevity. So, once again, do you think I need to install a lift pump?
  • Another component that I plan on installing, after I solve the no-start problem, is an upgraded fuel filter system with or without a lift pump (need your recommendation).
  • Are there any other upgrades to engine or transmission that you would recommend to help my engine and/or transmission be more efficient or reliable? I wasn’t even going to mention this because I didn’t want to “muddy-the-waters”, but I did purchase a PPE Xcelerator Tuner. I have not installed it and even if I do, I will only use the stage 1 tune which only provides the 40 HP increase. As I said, I have not even attempted to install it yet so this has nothing to do with the no-start.
In Conclusion:
I really need some help on this no-start problem and I’m open to any and all reasonable solutions. Here is what I have concluded so far. It seems I am not having any problem getting fuel from the fuel tank to the fuel filter without air bubbles. I believe (but am not positive) that I am even getting fuel to the CP3, but I don’t believe I am getting any fuel out of the CP3, into the fuel rails or high pressure lines. If you remember, when I replaced the FRPS, there was zero fuel in the junction box after weeks of attempted engine starts.
After reading this novel, some of you may say, “oh, I know the problem, this guy has messed with the injectors and he either has a leak at one of the injector return lines or a stuck injector”. Well, I can’t positively rule that out, but as long (for weeks and weeks) as I have been turning this engine over I will say again, there is no fuel in the oil. As for a stuck injector, remember these injectors have new nozzles and needles inside, no gunk to hang-up the needle jet. They all slid in and out of the nozzles beautifully; no sticking. Additionally there would not have been any fuel pressure to even get the needle to stick open. Am I wrong with that analysis; if so I’m open to be corrected.
Other possibilities could maybe be a faulty FICM or ECM, but what would the odds be of one of these going out at exactly the same time I switched the injectors, since they worked perfectly before? And for those of you that may think that I messed something up electronically when I charged the batteries; I either physically remove the batteries or disconnect the negative lead before I do any charging.
What I keep coming back to is some type of an air-leak between the fuel filter and CP3. I want to believe what “chevyinlinesix” on dieselplace.com forum says in a 12/27/2012 post, My guess is there is an air leak from one of the rubber hoses between the engine's quick connect fitting and the CP3's inlet fitting. It’s like I want to believe that, and as a result I have checked all of these lines, both high and low pressure, like six times and I just don’t see where there could be a leak. I will add that I did use SS worm gear clamps on all of the new OEM low pressure hoses; but as I mentioned, I doubled them up and turned the “flat section” under the worm gear 180 degrees. After seeing the cracked and dry hoses that I removed, which still allowed the engine to start, and then looking at the brand new hoses with double clamping; I just can’t understand how they would be leaking and the old ones weren’t. But still, everything keeps pointingto a problem that is preventing the CP3 to fill the fuel rails and high pressure lines. Could I have gotten a hold of a bad hose even though it was a GM OEM replacement, and what are the odds of that? Do any of you have any other ideas how I can definitively check the low pressure lines for air leaks?
Any and all help will be greatly appreciated. I’m almost at a point to give up my first-born to get the right answer to get this rascal fixed. My name is Gary and can be reached at 256-295-7895 or garywbrock@bellsouth.net .
 
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#2 ·
I don't want you to think I might be speaking out of turn but since you disassembled the injectors and installed different nozzles did you flow test them and tuned them to specs? I really think all of your problems are you injectors or did you fry your FICM somehow?
 
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#3 ·
no-start lb7

Thanks sfcjones for taking the time to read my novel, and no you are not out-of-line in asking your question. But as I mentioned before, I probably will have fuel flow differences in the injectors. But I guess my point is and my mechanic friend concurred, that that in itself should not prevent the engine from starting unless I totally garbled the reassembly of the injectors; and I can assure you I was as careful as humanly possible in the reassembly.
 
#4 ·
Was my first thought, too....injector reassembly error.

I haven't finished reading but want to toss out brainstorming thoughts....

Why are your batteries going dead so quickly? I never had that problem after injector installs. Yeah it cranked a bit but never to point of draining.

Look up injector cleaning and use that method to by pass fuel coming from the tank. Basically disconnect lines at quick disconnect and run hoses into a container of fuel.

I'm thinking your issues is injector rebuild. It's not overly complicated but everything else you've done seems sound. Also, it doesn't take much to foul your injectors with foreign material and it sounds like you sprayed into the injector line port which could introduce particles. I need to go back and read what you wrote to make sure. On one of my posts I left a picture schematics of injector parts, maybe that might help you.

I'm guessing you ordered form Wholesale injectors?
 
#5 ·
Also, I believe others have had faulty FPR right of the box. Vaguely remember reading a post similar to yours of not start and ended up replacing FPR again and all was well.
 
#6 ·
Hey, I appreciate the input. Yes, like you I have narrowed the problem down to a faulty FPR or air leak on the low-pressure side. And I appreciate everyone's suggestions about the injectors. And yes, I realize that after the injector upgrade my flow rates could possibly be all over the chart, but I will say again, I don't believe that new nozzles replacing used carboned-up nozzles is going to prevent me from at least getting the engine to start. Plus, I don't know how carefully you read my post, but when I changed out the FRPS in the fuel junction there was no, absolutely "nada" fuel in the chamber. All the new injectors in the world isn't going to fix that problem. I just can't seem to get fuel out of the CP3; but like I said I could be wrong. Is there a good way to check for leaks in the low-pressure lines other than just examining them and checking that the clamps are tight? Also, is there a safe way to purge the air out of the high-pressure lines other than cracking an injector feed line?
 
#7 · (Edited)
I wonder if it would be worth the effort to check for fuel at the injector level. the mere thought of taking the valve covers off is just a lot of work to crack the lines to see if you have fuel.
On Edit: You rebuilt your fuel filter housing, That would be somewhere to check. I have read that during the rebuild that someone else did something got put out of place...
 
#8 ·
So, lets narrow it down to no fuel to injectors and work backwards.

What would keep fuel from getting to injectors? Have you checked FICM connections? Try unplugging and looking at pins and re-connect.

Because it's easy I'd be taking apart the fuel filter pump and double check install and parts. The two bigger o rings need to be installed facing away from each other on the flanged edge. Sounds like it firms up so should be good.

A possibility is your CP3 is not building enough PSI on the fuel. Faulty FPR

Have you checked your oil for fuel contamination? Drop some on a white paper towel and look for fuel ring around oil.

Sorry, just thinking out loud and writing stuff down. Trust me, I understand your frustration and sometimes it helps to get others inputs to help you think.

Sounds like you replaced ball and seat in the upper part of injectors are you sure you got everything installed back correctly, lots of little parts.

I'll do some more thinking when I have more time...
 
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#9 ·
Once again, I want to thank everyone for the suggestions; keep them coming and I know that my original thread is really long, but I would really suggest you read the "whole" thing. Then I think you can really appreciate my frustration.
 
#10 ·
Your troubleshooting is a text book list of things to check and I'm going to keep the list handy.

With the extent of troubleshooting and care you obviously take in your work, I think you have a new componet that is not working.

I'm guessing back to the injector rebuild. The shops that rebuild them can charge what they do because the quality of the parts/work/tweaking is part of the price.

The injector "pros" buy the rebuilds from shops known to do good work and are basing their reputation on the quality of the subcontracted work.

Not slamming your workmanship but as bad as it sounds, I'd start at square one with a quality rebuilt injector.

Good luck with this
Jim
 
#12 ·
Sorry Guys I have been away for awhile but I am starting to have a little more time and so here goes:

These engines are electronic, a scan tool is a must, even a cheap one, you need to read your cranking fuel pressure. If there isn't at least 1500 psi while cranking the injectors will not fire and the engine will not start. You need to know what your cranking fuel pressure is. My guess is that it is low. I once replaced a set of injectors on my wifes 01 and the engine wouldn't start with the new injectors. After much grief, I attempted to start the engine with the valve covers off and found the culprit, a cracked body on a new injector. Problem solved. Is that your problem, probably not, but it could be something similar and probably related to your injectors. These injectors are an incredibly sensitive piece of machinery. Any injector service should be followed by testing the injectors on a test bench. Actually the injector should be tested first to see if the injector is worth trying to service. I personally wouldn't replace nozzles on an injector unless I was certain that the rest of the injector could pass the stringent testing of a bosch test stand. Last year a local diesel shop bought an injector test stand and agreed to test 15 injectors of mine for free just to learn how to use the machine. 8 of the injectors were almost new, 7 passed and one failed. the other 7 injectors only had around 40k on them, they all failed the testing. On a bosch test stand, the injector will fail if it fails to pass any one of the tests that is tested. The first test is a drip test of the nozzle, then there are return tests and others that I don't recall. Injectors that return too much fuel will not build enough pressure to start. All it takes is one injector returning too much fuel and you will have a no start condition. If it was me, I would pull all the injectors and have them tested. It will cost about 40.00 each. If you have more time than money, you will need to do a return rate test for each bank of injectors. If a bank fails, then you can continue on to each injector to find the bad ones. Do a search on how to do a fuel return test. In the end you will probably wish you would have just purchased a new set of injectors from Brent at LDS or one of the other vendors here that sells Bosch remans.
 
#13 ·
I would check your rail pressure while cranking to see if you even have enough fuel pressure to open the injectors. Pretty easy to do if you have access to a scan tool. Also back in April when I pressure washed my engine to do the same repairs as you I had a no start problem that turned out to be a bad crankshaft positioning sensor. I guess I got water overspray on it and shorted it out. It wouldn't hurt to ohm that out and see if it's bad.

Sent from my SAMSUNG-SGH-I317 using Tapatalk
 
#14 ·
Thanks fellas, I can’t tell you how much I appreciate the information that you are giving me. I knew that the Bosch Injector was an incredibly precise component, but I had no idea that just one small issue with just one injector would prevent the engine from firing. Okay, I have decided to bite-the-bullet and get a new Bosch set. Working on an LB7 is just too labor intensive to risk messing just one thing up on the injectors. Okay, now that we have that out of the way, there is still one issue dangling that could still be a big problem, which is what I was concerned about and what daltonschfill mentioned; do I even have enough fuel pressure to open the injectors?
Sometimes I can be a little dense, so bear with me. Are you gentlemen saying that you think the reason that I am getting a no-start is because of the injectors not allowing the high-pressure lines forward of the CP3 to fill with fuel and develop pressure? Or, is the lack of any fuel in the high-pressure side another issue entirely? Like I said, when I replaced the FRPS with a new one there wasn’t a drop of fuel that came out of the junction box after 7 or 8 weeks of attempted starts. I just need to be clear on this point. Just like I need to understand if a functioning FPR is absolutely required to get the engine started? I understand its purpose, but my question is; is it absolutely required to start the engine?
 
#15 ·
The reason that I need to know about the FPR is that I don't want to install injectors only to find out the new FPR that I previously installed is no good. As I mentioned in my original post I'm getting voltage to it and the 0090 and 0193 codes were eliminated when I installed it. I guess what I am really saying is how do you know whether or not the FPR is actually functioning or not with out actually running the engine. Because at that point, like I said, you would have to tear down part of the engine again to replace it again.
 
#16 ·
I don't know about the FPR however when i helped my buddy get his started after the injector change we had to break the number 7 high pressure line loose on the fuel rail while we turned it over to get fuel to the back of rail. His was the hardest one I've ever tried to start but after a video I watched on YouTube we broke the nut loose and turned the engine over until we got fuel out from around the nut and it kicked over once. Then we tightened it back down and she fired after probably 10 fake starts. The guy on youtube said there has to be a way for the air to escape before it will allow the fuel in.. I'm not sure if that's the case but I know it worked so you might just want to try it before you dish out that 5k

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#18 ·
I think it is time to call John Kennedy or Brent at LDS, I would think that a faulty FPR would produce a no start and you might be having several issues. Give either one a call and I think you might have a solution in hand...
 
#19 ·
You can bleed air out of the high pressure fuel rail by removing the plastic cap and depressing the schrader valve. A cheap scan tool would really help you out as you can watch rail pressure while cranking, make sure the ecm is seeing rpms (crank sensor) and other important functions. Brent at LDS is usually very helpful with troubleshooting problems.
 
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#20 ·
Hey guys, tears almost came to my eyes. You guys really do care. I'm going to try what you fellas suggested and I'll get back with you. Don't forget me though. It may be a day or so since my wife just had surgery and I feel like I have to help her around the house. I'll try some of your suggestions in between helping her. By the way, I do plan on getting new injectors (the upgraded Bosch factory type); who do you suggest I get them from. I know Merchant is good; I've also used Accurate diesel in the past, but I would like your suggestions as wel.l Thanks again, guys!!!
 
#21 ·
Also, it just occurred to me. I told you that I have a PPE Xcelerator Tuner (I have not used it yet); can't I use that as a scanner? I thought I saw in its user manual that you can have it perform certain engine tests.
 
#23 ·
the PPE should read desired pressure, and actual pressure. Brent from LDS is a great guy to get injectors from and is a vendor here. Merchant is also very good.
 
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#22 ·
Yes plug it in and run dtc test it will show codes. As far as engine tests my PPE programmer doesn't do any.
 
#26 ·
When my LB7 is ready for injectors I will be Calling Brent. No if's and's or Butt's.
 
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#27 ·
Okay Guys, I’m back at trying to get my Silverado 02 back on the road. Had some personal issues I had to take care of; my Mother passed away at 94 and my wife has had surgery as I mentioned before. Was having to stay kind of close to the house for several weeks. Anyway, I took someone’s advice and sent a very comprehensive email to Brent personally at Lincoln Diesel Specialists; I never received a response from him, just the offer to sell me injectors as you see on my thread. I’m sure he’s a great guy, but no one really wants to answer my questions. I’m really not trying to be an ass here, but are the questions just too hard for you fellas or are you just skimming my thread and not seeing them?? Okay, so let me ask them again and see if I can get some answers. Once again, before you try to answer these questions could you please read my original post (novel). I know it is long, but you really need to read it to see what I have done up to this point.

  • The first question is, when I pump up the primer on the fuel filter and gets it hard; is it supposed to remain hard over an extended period of time or is it natural for it to slowly lose pressure? The reason that I ask is that when I pump mine up and get it rock-hard it doesn’t take it very long before I have to pump it up again to make it hard again. The information on-line has been contradictory; some sources say that even on an engine that runs and starts fine, the fuel primer will slowly lose pressure, other sources say no, the primer should continuously stay hard. Which is correct?
  • The next question is a big one for me because the answer to it is going to determine whether I have a lot more work in front of me or whether I can simply focus on getting the engine started. The question is this; do you think I have a faulty FPR? I have tried to learn everything I can about the FPR and its role in the fuel delivery system. As explained earlier, I replaced the original FPR with a new Bosch sealed box replacement. And as I confirmed earlier I know that I have power going to the FPR and I further know that when I repaired the FPR connector I eliminated the 0090 and 0193 codes. So my question is this, can the scanner show that there is no code for the FPR but still have that FPR be faulty; and how common would it be that I would receive a faulty FPR from Bosch? If I have to go in and replace it I have to drain the coolant and tear the top of the engine down again; I really don’t want to do that based simply on “maybe” the new FPR was bad. It seems to me that here is another contradiction in regard to what I am learning on-line and in repair manuals about the FPR. According to what I have learned, the FPR doesn’t really regulate fuel pressure; it controls the volume of fuel to the high-pressure side of the CP3 pump. Okay, if that is the case, does that mean that it is absolutely essential that the FPR be functioning properly for the engine to start or does it simply mean that the FPR is absolutely essential for the engine to run smoothly and efficiently after it is started? I have read some diesel blogs where they are saying how they disconnected the FPR then ran the engine to test for other issues. Are they saying that yes, the engine can be at least started without the FPR being energized? The reason that this question is so important to me is that if the FPR is not absolutely essential to start the engine, then I have to look elsewhere for the no-start problem.
  • Okay another question, which is similar to the question about a bad FPR, is if I have absolutely no (zero) codes, could the FICM or CP3 pump still be bad?
  • Another question; or maybe this is simply a recommendation. Should I install an upgraded fuel filter system with a lift pump? Before you answer that question let me tell you what I need out of my truck. I will be using this truck pretty much for only one thing; pulling a car trailer for restored antique MGA sports cars (they are small). I belong to an MG club and we have meets all over the U.S. where we trailer in our cars. Just so you understand, I’m not pulling a huge fifth wheel travel trailer or anything really heavy, just a relatively lightweight trailer with a small sports car. Also, I’m not interested in modifying my engine to develop 700HP; what I am interested in is reliability and longevity. So, once again, do you think I need to install a lift pump and/or upgraded fuel filter system?
  • Are there any other upgrades to engine or transmission that you would recommend to help my engine and/or transmission be more efficient or reliable? I wasn’t even going to mention this because I didn’t want to “muddy-the-waters”, but I did purchase a PPE Xcelerator Tuner. I have not installed it and even if I do, I will only use the stage 1 tune which only provides the 40 HP increase. As I said, I have not even attempted to install it yet so this has nothing to do with the no-start problem.
I want to thank you fellas again for the help that you have given me so far and I really hope I have not offended anyone, but this problem has gone on for far too long and I really need your help.
 
#28 ·
I wouldn't spend the money on a lift pump. Lots of.guys swear by them, but if the engine needed one in un-modified form they would have one from the factory. As mentioned earlier, I would focus on what your pressure is while cranking. Once you know you have 1500 or more psi, you can then look at maybe the FPR is defective. On my LLY, we needed 10 psi at filter head and found we weren't building enough to fire the injectors.
 
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