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Reduced power mode, Then fuel filter display showed 94% to 0. said replace, then died

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30K views 30 replies 9 participants last post by  Dmax affair 
#1 ·
I was driving home Friday night and my new to me truck decided to have issues. It was running fine, then it started running funny and the message center displayed reduced power mode, then it went on to display the fuel filter at 0% and to replace, then just went dead. This all happened in a mile. I tried to prime the fuel to restart, no luck. Got her towed to my house as it is out of warranty with 107,000 miles on her. Went to get a filter at the GM dealer and talked toothier Diesel tech. He said it sounded to him like maybe the wif sensor and to replace it as well. They did not have one in stock so I had to buy a dormant replacement at Carquest. Took my old filter off, removed the wife from it and it looked different than the one from the original, well I assume it was the original. Placed it on the new OEM Delco Filter and installed on truck. Primed it and bleed it all off. No Start. Primed it again, no start. I did this several times, have not seen any fuel leaks, and it finally sputtered of for about 25 seconds and died again. It has not fired off again.
Is the primer plunger suppose to get really hard and not be able to press if it is primed correctly? As mine does not get real firm.
Any one else seen this happen?
Any help would be appreciated as I just made my first payment on this machine the day it acted up. Thx
 
#3 ·
Yes, the plunger should get pretty stiff when the filter gets filled up. Did you crack the bleeder screw on top while priming? The bleeder will cough and bubble while filling up, but then you should get a good bit of fuel once it is full, kind of like bleeding brakes except you don't have to keep closing the bleeder between pumps...

Sometimes it takes a bit of pumping to get the job done so don't be surprised if you have to pump it quite a few times...
 
#4 · (Edited)
yes, I loosened the bleeder and pumped until no air was detected in diesel fuel, closed, pumped primer till it got decently firm, loosened bleeder again and it let out a very little air and closed it, repeated that process 3-4 times. Then pumped the primer several times, turned over, no start, repeated 3-4 times, it finally fired off for about 25 seconds running roughly and then shut down. repeated the priming several more times and it has not fired off again.
How firm does the primer button suppose to get? Will you still be able to push it all the way down with a bit of pressure?


What would cause it to totally shut down in he first place when it needs a filter change? That could be very hazardous if on a major highway and/or towing something when you loose all power
 
#5 · (Edited)
First off, welcome to the forum! :thumb:

Sounds like the filter isn't seated and letting air in. If I remember correctly, there's an "O" ring around the top of the filter. Did the old one come off with the old filter. If not, that could the issue. Conversely, if the new filter doesn't have an "O" ring, that too would cause problems. Not tightening the filter enough could also let air in, but getting carried away tightening the new filter isn't good either.

Bottom line is it sounds like you have an air leak somewhere.

As for it shutting off before you changed the filter, it could be the old filter was plugged. Did you see if there were any codes?
 
#6 ·
I had a friend come over a bit ago to hook his code reader up and it only showed ERR on his reader for some reason. He said his reader always pulled a code, but he has never used on a diesel, does that matter?
 
#7 ·
It's likely a "manufacturer specific" type code, some cheapie code readers will not read codes of that type. I know mine doesn't.

To tell if its a manufacturer specific code once you do recover it, it will be P1XXX if I remember correctly. A SAE code will be P0XXX I beleive.
 
#8 ·
When priming it, I do not see any fuel leaking from anywhere as if a seal was not sealing right. I will remove and check this evening when I get home though.
What could cause the initial low power mode, then flash up the filter needing to be replaced then shutting down?
 
#9 ·
CP4... time to remove the FPR and look for metal.
 
#10 ·
Ditto on the CP4
 
#12 ·
The fuel pressure regulator is on top of the injection pump deep in the calley of he engine. It can be removed without any major disasembly with some patience and finesse. Two T20 screws secure it on top of the pump and a electrical connector on it aswell. I usually unbolt the fuel test port fitting and pop the return line junction out of the clip to remove the regulator.

A magnet, long 1/4 inch extension and a long pick are very helpful to getting it out.
 
#13 ·
Having the code associated with the check engine light would be a big help for everyone.....just saying
 
#14 ·
Here is the list of codes AND DESCRIPTIONS IT SHOWED:

P128E MANUFACTURER CONTROL FUEL AIR METERING

P0087 FUEL PRESSURE TO LOW

P049D AUXILIARY EMISSIONS CONTROLS

P0403 EGR FLOW CIRCUIT MALFUNCTION

P122D MANUFACTURER CONTROL FUEL AIR METERING

P02EO FUEL AIR METERING

P140A MANUFACTURER CONTROL AUXILIARY EMISSION CONTROL


what Do these codes mean? EGR went south and shut everything down?
 
#15 · (Edited)
ok cleared the existing codes, cut ignition off.

tried to start it for like 10 seconds, pulled codes again and here is what came up:

P140a manufacturer control auxiliary emission controls

p245a EGR cooler bypass control circuit


still not starting


Any ideas?
thx
 
#16 ·
The only reason the emissions codes returned is that they did not clear - the truck needs to be driven once the failure for those codes is adressed to have them clear.

The other codes that did not return the engine has to be running and or other conditions need to be met for them to set.

With you having a low rail pressure code (P0087) I'd still be pulling the regulator #1 on top of the pump.
 
#17 ·
Could the low pressure code come from it loosing prime? I see no fuel leaks or collapsed lines anywhere, I still cannot seem to get the prime pump button to get to hard to pump.
1)Can the fuel be returning to the tank through the return line? Is that even possible to flow through the high pressure pump to do this?

2)Could an injector be hung open and allowing this?

3)If the seals in the primer pump are bad, is it possible that they not leak when pumping it?
 
#18 · (Edited)
They seals will go bad in the fuel filter assembly and it will cause a soft pump. My 2005 would still prime, but not as easily. I replaced mine with a kit that can be purchased, but when it was all said and done, it would be easier to just buy a replacement fuel filter assembly, as they are not expensive and it saves a lot of work..............not sure if it's different for you 2012, but mine was a 2005.


I think you need to get that thing into the dealer and see what they will do and also contact GM Customer Assistance and put them in touch with your dealer. I did that on a water pump that was just out of warranty for a month or so and GM gave me the parts and the dealer discounted the labor.
 
#19 ·
Well I got the call from the dealership...worse case scenario. hpfp went out and the whole fuel system needs replacing.......

Anyone know of the best place to buy all the replacement parts so I can do it myself, and does all those parts really need replacing? How come the fuel rails have to be replaced? Can they not be cleaned? What about the Fuel injectors - Does not the screens on them keep the metal out? I understand if it was under warranty demanding all that being replaced, but is it neccessary?


Or will doing a CP3 conversion be my best option, only want a running truck again, not trying to go overboard modifying if I do convert.

What all does it entail to convert to A CP3 SETUP?
 
#20 ·
If it was me I wouldn't want to risk repeat failures by not replacing all the parts. The hard lines I might consider reusing, but rails, injectors and I/P for sure. We are also told to drop the tank, drain and clean it.
 
#21 ·
I would try working with GM. They may cover the parts and you the labor.... Did you buy this through a private sale or a dealer? If it was a dealer I am sure you would be able to go after them for the repairs since you only drove it 400 miles...
 
#22 ·
From a reputable dealer I think, been in business over 50 years. Hopefully this will not tarnish their image as I too would think they would help out in this situation more than they normally would.
With these going out like they do without warning, it is an actual hazard to life and limb, imagine towing a dozer and going down a hill and it pooping...no brakes, etc....it would get really ugly really fast. Hopefully no one has to die for them to fix this issue.
 
#23 ·
Good luck and hope you get help for the $$$$. I hear $9k as a common dealer warranty figure.

With the LML it is increasingly important to add preventive measures. We've been selling the CP3 conversions for these. Unfortunately it's usually after the fact. I am contemplating doing mine before too long.
 
#24 ·
Talk to your dealer and work your way up the chain of command, starting in service. If they can't / won't work with you, ask for an appointment with the factory rep. Yes, at 107,000 you are out of warranty, but I'm betting they will work with you if for no other reason than customer relations, especially if you are a repeat customer. Additionally, if they do the work, it comes with a warranty. I bet they'll offer to split the cost at 50/50, maybe more depending on what the issue is. :thumb:

It's one of those things that costs nothing to try, and BTW: be cordial, the old saying of getting more flies with sugar than honey applies. :HiHi:
 
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#25 ·
Kennedy,

What's the typical cost on the CP3 conversion install including shop labor? I am contemplating it, but probably wouldn't do the work myself.
 
#26 ·
In my opinion, GM should warranty the parts and dealer should discount labor. If you could get the work done for $4-5K, it would be a reasonable deal. Less would be a great deal. Anything else and your getting bent!
 
#30 ·
It's almost as though I were the GM rep. :eek:


Good on ya! I am glad it won't be so painful. :bounce:

As Kennedy said, maybe do the CP3 conversion. Especially if your keeping it a long time. Other things to do is make sure you have a lift pump and run a lubrication additive in your fuel or biodiesel.
 
#27 ·
Does the dealer you bought the truck from do any form of optimum inspection on their used vehicles? I know my used car department if there's an inspection done there's I think a 5000 KM 3 month warrenty. Was anythingn mentioned to you when you bought the truck?
 
#28 ·
Well I just received the call from the dealership, I was told GM would cover 40% of the work that my truck required as a warranty deal (thank you GM for standing up and taking care of some of this), and told me he estimated 4500.00 and it comes with a 12 month/ 12 thousand mile warranty on this.
Don't know if I could do it cheaper, but the warranty and a certified person doing it is worth something I would think.

Once it is taken care of, what would be the best course of action to help prevent this happening again? Adding a fass lift pump?

There is one thing that I think we all can take away from this, is that there is certainly a major issue with the CP4 or GM would not of help on my issue, I am sure. Bet a recall will eventually come. (hopefully)
 
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