This starts out as a continuation from another thread linked below, after the horn fix the thread was departing from the title heading, so I moved part of it here; might make it easier for someone to look up later.


Turbine Doc


Starting out GMCTD is describing hook up of a boost fooler, rest follows as added to the original post http://dieselplace.com/forum/forum_posts.asp?TID=15935&P N=2


Lead in with CR comment "Maybe get some time today to also hook up that fooler correctly, how do you normally tap into the B wire, no 3 way connectors out here in the Brazeau?"


GMCTD reply:


Seperate the B wire, leaving enough on B to connect to your pot wire.


With potentiometer shaft facing you, three terminals pointing up -


Wire from top right pot terminal connects to that short wire on B.


Wire from pot center terminal connects to that cut wire in the harness from the PCM.


Wire from top left pot terminal splices in to the ground wire on A.


Shaft rotated fully CCW is oem Boost setting.


Shaft rotated in CW direction is increased Boost setting.


Shaft rotated mostly CW is DTC for Boost over-range - this one will MIL\SES about 20secs into a hard pull.


Shaft rotated fully CW is DTC for Boost\Baro Sensor out of range - this one will MIL\SES soon as you key-on, and anytime the engine is running.


Correct adjustment range is probably limited to 1/2 turn from full CCW position.


Starting from full CCW, adjust slowly till you get your range spread.Edited by: Turbine Doc

CR,


Are you putting it under the hood or on the dash?

In the dash. Just melting a few plastic parts here.


Damn this thing... I just reved it up and its like it wanted to run away for about a second and then calmed down. Been giving me these hicups like that.Edited by: CanadianRigger

How long has that been going on?

If memory serves me correct i think since the 'bump'... i made mention of it in another post but no answers


Sorry for the delay since the forum upgrade i don't get emails of messages anymore and it no longer shows new unread posts???

That's what I was thinking, far as events chronology goes.


When you get a chance, 'un-bump' it and see if things settle down to normal.

I never responded because I never could determine any connection between the two. By all means, if you can determine thats the cause let me know. I have done this before, so don't think that any of you guys here on the website are my guinea pigs. I would never suggest anything to anyone that I believe could cause damage, I'm here to help not hinder.Edited by: Texas Diesel Guy

We just need to start from a known baseline, TDG - see if we can restore his truck to operational, then proceed from there.

I never responded because I never could determine any connection between the two. By all means, if you can determine thats the cause let me know. I have done this before, so don't think that any of you guys here on the website are my guinea pigs. I would never suggest anything to anyone that I believe could cause damage, I'm here to help not hinder.





No problem TDG, i know you wouldn't intentionally suggest something to someone that would harm their truck and if the potential was there i'd assume you'd warn them first... eg: like bumping the optic too far, what could possibly happen then? Myself i have no idea if it could hurt it so i would count on what you and others would say and base my decision on that. If for some reason that has screwed something up on the pump then its my loss as it was my decision to do it, nobody twisted my arm behind my back. http://www.dieselplace.com/forum/smileys/smiley1.gif

I've read a couple people say similair comments as you GMCTD, but I contest that we ARE starting from a known baseline. Very simiar to giving the old DB2 pumps a ¼turn on the leaf spring, you know your at stock and you know your going up from that, maybe not exactly to the CC how much, but you know you have increased and know what you have to do to get back.

The baseline does not often include 'run-away' rpm, and particularly when the engine was not dong it before any modifications.


Not to suggest that he shouldn't try the mod, or that it is bad - just restore the original normalcy before proceeding.


I personally do not think the mod will result in much improvement if the camshaft is retarded from worn timing chain, which means the inj pump is also retarded.


Timing motor could be advanced to limit trying to compensate for retarded timing drive set - pump TDC is way behind crank TDC.


TDC Offset could be positive (up to 2deg), Actual timing could be 0deg - low power, no DTC's


Hi-mileage injection pump may be out of flow bench spec, and worn injectors would already be dumping 'advanced' fuel due to lower 'pop' pressure.


Add increased fuel from a mod, and the PCM will not be able to keep up with Cylinder Balance routines


Too many unknowns - adds to already dangerous 'run-away' rpm.


Edited by: gmctd

Timing chain wear DOES NOT retard pump timing on an electronic DS4 pump. Advance movement is calculated against CPS signal so any slop is compensated for, only cam/valve timing is retarded. Setting TDC offset is also compensated for wear because its timed against the Crank sensor. Again, I set ALL the DS4 pumps I build about 1½-2ccs higher than spec, compensate for it with lower resistor numbers and have had 0 problems and have had several praise the improved responsiveness, power, and quicker starting. No complaints of any surging, cyl contribution problems or change in fuel consumption. This is a tested and tried method, yes, I will admit, its best done on a test bench, but this pump is MUCH more lenient than most people think and can safely be attained on the vehicle.

Explain the 'run-away' since the 'bump'..........

Okie dokie


To start with when sitting idling for 5 min's or so without touching anything it will suddenly give a short surge of maybe 100 rpm, only lasts for a second, kinda like a gasser would do with a bad plug that decided to fire once all of a sudden and then quit again.


Now the run away is different, after idling for 10 - 15 min's its time to rev it up and clean it out a little as i have no hi idle yet, you know maybe rev it to 1600 or so a couple of times, well the first time i step on it after slobbering for awhile i let off and it carries on, maybe 2500 rpm or so, once again only for a second or two and not every time i rev it up after slobbering?


I've also noticed alot more rattle with the pot hooked up, normal? good? detrimental?


With my new website i am able to upload pretty much anything, video, sound, whatever, when i get the time (who knows when that will be) i'll try to catch this thing stumbling, don't know if it will help but i'll put it up with a link for added help. I've always said that i think there's a dead miss to this thing or close to one, today it seems to be a little more pronounced but it could just be me. What can i run through it to clean out the pump and injectors with just 1 tank of fuel, something real good that i can get here and not to harmfull?

CR - I meant for TDG to explain, in his own words, the causitive for the problem you've been seeing since the 'bump'.


Problem which you've just very aptly described - it is appreciated, dude.


It has been suggested, in other posts, to check the Timing Stepper Motor for being at maximum limit, indicating PCM is calling for maximum advance, but cannot get it.


Which would require loosening the inj pump and advancing it a bit to bring pump timing back within factory spec limits.


Which is done to compensate for retarded pump with loose timing chain.


So the Timing Stepper Motor could function within it's design limits.


Which is oem factory recommended procedure to improve 'driveability' on vehicles with hi miles.


(At same time, customer should be advised of necessity to have the timing set replaced, to restore full 'driveability'.)


And explain what would be the necessary requirements to restore 'driveability' for a 'bumped' inj pump that was not on his flow bench, fresh from rebuild and being adjusted to meet tested requirements.


Say - a 'bumped' pump with high mileage, probably at the end of it's useful life, being driven by a loose timing chain, supplying worn injectors, all well past oem recommended replacement spec.


Where vehicle 'driveability' had been compromised by an adjustment to the Optical Sensor.


An adjustment affectionately known as - 'the bump'.


Just wanted to get an explanation that did not continue to refute all previously posted information on inj pump operation, and function within a 'system' - i.e., on the truck.


See, my memory is acknowledgeably bad, so I copy 'factual' data over to Word, correlating it to subject and topic, deleting names to protect the innocent.....


In short, a training manual which can take on epic proportion - at least, until I see absolutely conflicting data in later posts.


Then, my 'training manual' takes on "Mad Magazine" aspects.


Who ya gonna call............ghostbusters?Edited by: gmctd

In short, a training manual which can take on epic proportion - at least, until I see absolutely conflicting data in later posts.


Then, my 'trainig manual' takes on "Mad Magazine" apects.


Who ya gonna call............ghostbusters?





NOW WHAT "FREAKIN" GOOD WAS THE LAST PART OF THAT POST?


YOU WANT THEIR NUMBER ??


Your Ball

Sorry, thought you wanted a more detailed description of what its doing, oh well, at least everyone knows now... lol

You done good CR - point is, your system is not fresh, so 'unbump' the pump, see if it recovers.


Then, we can start over, with TDG's input.


And, sure, bowtie - if you think it'll help...http://www.dieselplace.com/forum/smileys/smiley2.gif

I was having fun, CR, and overlooked your further questions.


No Boost required at idle, so pot cannot make a difference in 'rattle'.


Cooler weather calls for more advance, with more pronounced 'rattle', and longer glow duration - possibility the 'miss' is a failing glow plug.


Also good possibility the miss is first sign of failing injector(s), not atomizing the fuel, but injecting it into the cylinder in a stream.


Can result in a 'holed' piston over a period of time.


Check the glow plugs first - just remove each one for visual inspection - no swelling or burnt-off ends, and check each one for ~1.2ohms cold.


Kennedy Diesel sells a replacement that always gets excellent reviews - SLM, iirc.


Can also unplug the Engine Coolant Sensor, so PCM will think it's -20deg outside, and will extend glow time to compensate.


Will also give you 'bad boy' advance, so the engine will be really noisy, but it should eliminate the 'miss', if injectors are up to the task.


Can run some Stanadyne or Power Diesel Service cleaner to see if it will help.Edited by: gmctd

CR,


When my fuel solenoid started acting up, I found that I couldn't hold the idle at 1000 rpm in P. It would do as you describe and rev higher and then eventually settlte down. It went with a new pump.

I can hold just about any rpm steady with the peddle, its a very short run away, but it just shouldn't do it. I may finally get the time today to 'unbump', i won't go back to the stock setting but should come close. See what happens with that.


Boost control works great, i set it about mid pot for start and driving, holds 7-8 PSI @ 70 mph+, climb even a small grade and it climbs to 12-14 psi, i turn it down to 10 on the hills and put it back to mid pot for cruising. I wouldn't think i'd have to worry too much with the 4" exhaust but going to play it safe until the pyro is tied in. A few seconds of 15 psi shouldn't hurt though should it?


One other thing, man can that turbo sing!


0-60 in 15 seconds flat.

CR,


Running empty with the 4" tube you should be okay occasional bursting to 12-14, you don't want to tow there or run sustained at that level. 7 Psi boost is plenty of boost for what you are doing, even with all my stuf I rarely run there 5-6 is what I cruise with, post IC, I've never measured but I think I'm maybe 2 psi drop across the IC.


IMO IC better for sustained towing, WMI for racing and occasional tow probably better bang for buck but more maint with WMI, IC is install & forget other than occasional tube connection checkups have to do a pro & con analysis for your particular situation


on your 0-60 you staging up at all or just going from standing start not revving up engine; I ran 14-15 in stock when I 1st got it, haven't really checked after mods just to know it's making power when I need it is all I care about

Under normal circumstances, PCM will cut boost if over limit for 20 seconds, and also if Intake Air Temps get above ~240deg.


So, yeah - you're safe for a bit, but the EGT gage is an absolute necessity now.

Yes I'm staging for the 0 - 60. Try to get it to just before wheel spin on takeoff, usually when i take off the kid pulling the little RED WAGON passes me http://www.dieselplace.com/forum/smileys/smiley19.gif


What are you guys using to monitor IAT's, that will be next on my list of must do's.

If 0-60 times are what you are really after, staging the truck against the converter may not be your best choice.


Try holding RPM just above idle, then floorboard it. You would actually be 'Flashing' the torque converter and achieving a higher stall speed. What you are doing now is 'locking' the converter and that is why it is falling on its face when you leave.


In theory it may help, provided you can prevent excessive wheel spin.

Monitoring IAT with my Snap On scanner, but will eventually mount a RTD in the inlet plenum, any temp sensor will do look in Jegs, Summit, Whitney's etc has senders for oil-trans-fuel temp that will work, I'm looking for a dual needle one used in aircraft world to monitor IC in and IC out for my IAT, just getting up $$$ to do it.

Since the IAT sensor on the truck reads known temps as known resistor values, it would be really simple to wire a series of LED's on the dash to light up to corresponding temps. A take off on the LED light boost guage.


Same values as other sensors:


113*F = 1188 ohms


122*F = 973 ohms


140*F = 667 ohms


158*F = 467 ohms


176*F =332 ohms


194*F = 241 ohms


212*F =177 ohms


230*F = 109 ohms


As the ohms lower the temp rises.


Edited by: quantum mechanic

Got to agree with Bill on that from my own experience, one thing I noticed was "better" launch/higher rpm with "bad" brakes, after I installed stainless flex lines, drilled rotors and hi perf pads up front, and adjusted rears so they hold better & result in less rpm wheel spin my launch rpm/boost is lower than before with the "bad" brakes.


I don't know if it effects 0-60 I haven't checked as I said before. Wet pavement or going arond a corner where wheel spin allows rpm/boost to come up I'm a little crisper off the line, but how much traction slip is too much.


Since I have no experince in racing Diesels I'd be hard pressed to give an accurate opinion, just observations of what my truck does.


Bill Heath who used to drag race Diesel trucks said hard to do a good "launch" with trans as set up by factory.

Wasn't the complaint that it would leave the line ok, but fall down at mid-to-upper rpm range?

Wheel Spin? Whats that? This truck won't wheel spin on hard gravel from a standing start.


Here's some pics of the latest before & after bump, no change in performance, maybe a little less smoke when reving it up.


Before


http://www.dieselplace.com/forum/uploads/CanadianRigger/2004-10-06_121247_Bump_Oct_6_0001.jpg


After bump


http://www.dieselplace.com/forum/uploads/CanadianRigger/2004-10-06_121343_Bump_Oct_6_0002.jpg


And the Boost tap from the inside,


http://www.dieselplace.com/forum/uploads/CanadianRigger/2004-10-06_121452_Boost_tap2.jpg


Lines are for your reference. Where do i go from here?

It almost sounds like you have a tranny problem. I mean my N/A 6.2 would spin 35" tires on gravel. Is there any way that maybe your tranny isn't going to first gear, oh course I am assumimg that you have an Automatic transmission, the 4L80E. Any thoughts about this, anyone know the first gear ratio of this transmission?

first is somthing like 3.12 :1.


If you can't spin a tire in first somthings wrong. My dad's 96 can scratch evertime you give more than 75% app , my 94 you have to floor it to scratch.

I said HARD gravel, you know, the two well worn strips in the main traffic area. It will shoot some loose gravel, but not for long.


I'm almost positive the tranny is fine (auto), it shifts well, all the shifts are there and goes into lock-up after. It does not slip. Personaly i think i have this optic way outta wack.

Loosen the torx, move the sensor as far to the drivers-side as it will go.


To the passenger-side of the sensor you should now see a line scribed front to rear across the camring - move the sensor back to that line, where you can still see the line, tighten the torx, seal it up and run it for a while to check for run-away.


That should be where it was set at the factory - at least on my pumps, OBD-I and OBD-II vintage.


If it is healed - take your flashlight and look down in at the timing stepper motor, low passenger-side front on the ip.


Up - retract - is advance.


Down - extend - is retard.


If it is hard up retracted, PCM is calling for advance it cannot achieve because of extremely loose timing chain.


If it is way up, but hunting up and down erratically, PCM is trying to compensate for loose chain flap, but chain has not reached a point past PCM capability to compensate.


Either way - time for new timing set, which will restore lost power (see TDG's post on timing set replacement).


Now - anybody wanna see my Official Ghostbuster's Membership Card and Signet Ring?


We do gremlins - electrical AND mechanical - and things that go 'bump' in the night..........http://www.dieselplace.com/forum/smileys/smiley16.gif Edited by: gmctd

Thanks for the info gmctd. I will do that tomorrow. Sure hope that mark is there.

Anyone have a pic of this stepper motor? I'm not 100% sure of what i'm looking for here.


Will be doing the bump thing again right chicken Louie here. Will post results when done.

The part you're lookig for is at the bottom of the stepper.


http://www.dieselplace.com/forum/uploads/quantummechanic/2004-10-07_075402_stepper.jpg

Your stepper will have an additional black metal bracket in the rod area - it is a shield and limit stop.


You can still see the rod, tho.


Excellent show and tell, QM, as always.


Got a pic of the camring, where the line is visible to the left of the sensor? Edited by: gmctd

I have a pic, will upload shortly now that i know what i was looking for. Did the bump back, i thought the smoke i had before was normal, now i have practically none. 0 - 60 seems to be the same but at least the optic appears to back to near normal. Will check the stepper shortly also.


Thanks GM & QM for your advise, pics to follow soon.

Here's the pics, Note the scribed line.


http://www.dieselplace.com/forum/uploads/CanadianRigger/2004-10-07_103031_Optic_Restore_0001.jpg


Note the barely visible line at the bottom of the sensor.


http://www.dieselplace.com/forum/uploads/CanadianRigger/2004-10-07_103308_Optic_Restore_0002.jpg


This is after bumping it back.


One more thing also. You know the clips that hold the wiring plugs in place... lets just say i now have 2 of those that are going to have to be a friction fit now. Hope they don't rattle out!Edited by: CanadianRigger

CR


If rattle out becomes a problem, put heat shrink sleeve over the connector, here is another thing under hood heat will shrink the sleeve on it's own, you won't need to put a heat gun on it.Edited by: Turbine Doc

I will have to remember that if they come off.


Well, seems i've cured the run away problem so far.


Now back to getting more POWER!


Can i put hi pop hi flow injectors in with my current pump? Will it make a difference without upgrading the PCM?

They can, but if it were me I'd save for the reflash 1st, hi pops are not much less than reflash, I'd flash 1st before inj, you towing much with this thing, if not WMI might be a good thing, if managing water and maintaining nozzle/pump/switch will be a chore for you then go IC, more $$$ but a set and forget system.


Putting optical back to factory go rid of runaway???, one of the things I do whenever going on any turbine trouble call is get a rundown of last maintenance activity, if a problem occurs right after the activity "it was running fine until" I start digging into how a particular maint activity was accomplished, many time to annoyment of site folks un-do what they just did, usually find they almost did it right but not quite.


It's possible I guess from success TDG has had with that, you may have gone too far with 1st move, or there is a underlying problem exposed when you did the optic sensor move; have to let him weigh in on that, since I've never done this myself.Edited by: Turbine Doc

So.... What's his next move?

I tow every now and again, 27.5' 5th wheel. Yes putting the optic back got rid of the run away completely now, i didn't put the optic so i could still see the scribed line, i put it so the line was just covered, if i'd known that line was there i would have done as GM suggested a long time ago. No more power, no less power. Now when i throttle it up sitting still the smoke is almost gone, TDG had said more smoke was good and meant i'd made the right move to adding more fuel, "perfect" in one of his posts was the words he used. I may try to adjust it one more time to see if it makes a difference but i'm not in a hurry to do it now.


I don't think WMI will work well for me in my application, always out in the bush working, stuff freezing etc, 100 miles of gravel roads every day, gets pretty rough on the truck out here.


I am looking into setting up a intake cooler with liquid N2 (-196C) or liquid C02 (-18C @ 300 PSI) and pulling my air in through there, would be much better than air/air. What do you think?http://www.dieselplace.com/forum/smileys/smiley3.gif

If injectors are bad and not poping correctly, possibly streaming fuel rather than atomizing, would i not be better off doing that first? Save some pistons?

How many miles on your injectors, if you suspect them find a local inj shop and pull a few (or all if you like and have them cleaned /tested), make your decision based on those results, I pulled mine at 70K nothing wrong with them.


Wanted the extra power, & at the time there wasn't a good bang for buck reflash so I did Inj before Reflash, that changed with Heath's latest offering, now I'd reflash then hi pops, even with hi pops/flows you are still at mercy of GM's program which clips fuel and boost just when you want them most.


Check around you will see HP injectors and reflash in same $$$ ballpark, reman stock Inj are about 1/2 cost of Hp but if yours are still flowing okay which I suspect they are in a low mile 2000 model, more reason to check into reflash.


All that said you need to keep IAT under control both programs including reflash with clip on high IAT.


As for WMI since you say you are out in the boonies often it might be the better choice than IC, mix a little alcohol in the water if freezing is a concern.


Unless you do a custom grill install, ICs in ready to install kit form are under bumper mount, which may not be best for offroading, If my truck were used often for off road I'd look at a way to armorize it. It's pretty robust but not suited IMO for serious offroad or frequent unimproved road conditions.


I don't see it in your sig; & you are worried about burning holes in pistons, are you monitoring EGT, if you aren't monitoring that do nothing else until you get gages.


Turning up the wick injectors/reflash or adding more air through fooling or TM takes GM design/PCM out of the safety loop that keeps you from hurting the engine.


Your noggin; that PCM on top of your shoulders, becomes the main PCM controlling the right foot go fast control when you start doing mods & moving away from GM design expectations; without gages you can't make good decision when you need to back off.

EGT is gage installed, just need to drill a hole in manifold and install the sensor. I do push this truck to 15 psi just cause it sounds so cool, hard not to when you can. But i try not to leave it above 10 for more than 5 seconds or so. 165,000 km's on her now and 200 or more every day.

If I did my ga-zintahs rite that works to 103K more or less mi, not too high but maybe a flow check of injectors is due. While monitoring boost do you see it spike to 14 then cut back on it's own, if so since you have a fooler that is high IAT knocking you back.


Do you have a good DVM(digital volt meter), if so you can get from Sears a thermocouple and 4-20 ma converter that will allow you to read IAT. At AC&R shops you ca also buy a dedicated remote thermocouple rig, the Sears one is pretty handy though.


Slip the sensor tip in by the upper inlet boot off of the turbo outlet, and put on 2 long wires on the signal converter so you can read temp on the DVM in your truck. This is a temporary rig though, as the tip of the probe is just a chromel-alumel wire loop and could break off and go to the engine.

Nope she's never cut back on her own yet, i've cranked the pot all the way up and in the last 1/8 turn it just cuts out the turbo completely, weather i'm doing 100 or doing 5 MPH. I have an digital Kingdom Pocket Dmm

Nope she's never cut back on her own yet, i've cranked the pot all the way up and in the last 1/8 turn it just cuts out the turbo completely, weather i'm doing 100 or doing 5 MPH. I have an digital Kingdom Pocket Dmm


Possibly a dead band in that pot at that end of the wiper, that DVM should work might have to make some jumper leads to connect it, I made mine from splice crimp connectors, un crimped on one end other I slipped on the 4-20 ma converter connections, ran wire into cab so I can read any temp I'm interested in, zip-tie the converter in an out of the way place, probe wire isn't that long.

if the injectors were weak enough to cause a problem, you would notice a rough idle and white smoke. Did you ever get a chance to see where your TDC offset is set at? Remember that boost alone does not make anymore power, until your get more fuel that air is not helping you any.

You can add all the boost you want but unless there is additional fuel which a stock computer wont supply you won't get the benefit of it. A heath reflash will give you about 20 percent more fuel and the fuel curve is totally reworked. I't a great addition to increasing boost. The only problem is your fuel mileage goes down (can't keep the foot off the pedal).

Doesn't really have a rough idle. No white smoke, nobody around to check TDC. No boost alone won't increase power without the extra fuel, that would be the fuel from the "optic bump", done as per instructions, over and over and over again. Maybe the stock computer won't supply the extra fuel but wasn't that the purpose of the bump? Fake out the computer so it thinks its stock? All i got out of the bump was a hell of a lot of black smoke when reving it up, just a little when driving it on the floor. Maybe timing is out to lunch, maybe the chain and gears are hooped, GM dealer put in a new PMD around 135,000 kms, wouldn't the timing have been set then also?


Thanks to GM for making it clear on how to put the optic back to stock. Very much appreciated!

With 16 psi and no intercooling, you've increased the velocity and tempature of your aircharge but lowered the O2 content relatively speaking per psi increase. This means the more you throttle it the less efficient the cumbustion is, as the aircharge climbs in temp and lowers in relative O2 content.


At this point adding a chip would be throwing fuel on the fire. The increase in heat will aid you little if you can't reduce the ~220* F temps the IAT is already seeing above 12 psi.


Have you tried your run with the lid off the airbox?


Edited by: quantum mechanic

Dealer should have timed it but could have done it wrong, mine was at 4.8 forever before I figured out how to change it. Another thing TDC offset if set by dealer will be at factory spec -.25 & -.75 doubt they kicked it up to -1.5 or -1.94.


Call around find someone with a Snap-On scanner with cartridge covering your year and willing to let you do some playing, MT2500 more common in small shops that have to buy their own equipment than a T2 found in every GM shop. print out the FAQ post on timing set, read it over shoot me a PM if you have questions how to do it.Edited by: Turbine Doc

OK. After CR gets his TDC offset at between -1.50* and -1.90* btdc what should he set his actual timing at? It should be +3.5 deg stock iirc what whould be a power setting? waiting for some feed back on this.

Taking off the airbox cover? I could try it and see but i would have thought the air coming in from the fender would be cooler than under hood air? Good point on the lower 02 content but, (yeah here comes the but again). I have seen no increase in anything from my first mod (exhaust) or any mod after that, you can't tell me that i shouldn't have seen something, anything, even a little?


Somehow i'm going to have to get the timing checked on this thing. Now if i could only see that stepper motor... may have to find a mirror.

It's on the passenger side of the pump and I can see mine looking under the watercrossover with a flashlight.

Stock timing is 3.5 * avg with time set/command at 0, on a scan tool command would read 0, and actual of 3.5 avg may "hunt" above & below, worse if not at spec idle 850rpm, smokes and stumbles bad lower you go in idle worse on cold days, I think you need a fully warm engine >170 f H2O to do this check properly.


CR I run with the lid off the box in winter, on in summer under hood air is hotter than what is coming theu duct, but duct is restrictive, I pop the filter blocked indicator everytime with the lid on, off I don't pop the indicator. On my to do list is a rework of that whole air box set up we have, those hard 90* turns into the turbo can't be a good thing, at least with your HD L65 you don't have honeycomb of MAF sensor to suck thru. I've got Bill H running me a "special" L65 tailored just for my L56, if all goes good L56ers may be able to fully cross over to L65.


Edited by: Turbine Doc

Hi ya'll, been a couple of days here since my last post and besides i've been to busy to post, i've had some other issues with my server and administrator and as they say on that apprentice show "Your Fired!" Bad thing about all that is now i have to rebuild my entire website from scratch.


So now if you'd like to send me an email you can send it to diesel@canadianrigger.com (cool)


Or just send me a PM on here.


Back to the issues... Today was my first opportunity to do another 0-60 run, (17 seconds) very, very depressing. Its obvious now that bumping back the optic has made this change as there were no other changes made since then, but hey its no longer 15 seconds...


TDG i would like to here from you on this, the optic is in its stock position as picture in previous posts.


I found the stepper motor also, very hard to see on the 2000 but its there. I watched it on start, shut down and while reving the engine hard, it moves very little but definately moves, its also in about the same position as picture on QM's pic. No hunting or pecking to find a sweet spot. Does that suggest the timing chain etc. is fine then?

Someone might have already asked, but is it possible that someone re-geared it to 3.42 or higher?

doesn't take much movement to make big timing change, the less 'hunting' the stepper has to do the better. I'm glad to hear that the optic adjustment did make a definitive performance difference.

I am the second owner of this truck, i doubt the gears have been changed it was on warranty most of the time before i got it, and if the gears were changed i doubt i'd be running 2500 rpm @70 MPH but i could be wrong.