2004 8.1L trying to go back to stock ? new guy to this

[terry735001]

again thank you very much DGS

the 2001 02 03 motor did have the fuel pressure regulation on the fuel rail and did run off manifold vacuum
in 2004 fuel pressure regulation was remover from the fuel rail and installed in the fuel filter
the fuel re-tune line was all so remover and the case for the fuel pressure regulation is empty
this is why you see the manifold vacuum line caped off

2 pics are 1 with and 1 with out the fuel pressure regulation

81xvHPo+8GL._SL1500_.jpgs-l1600.jpg

BUT this setup does let the fuel set at the motor and gets warm . but never hot . my setup runs cool
what i cant test for is to see if there is air in the line like if there is a pin hole on the vacuum side of the fuel pump
but the misfires are when the system is cold and go away more when it gets up to temp .
thats why i think some of my fuel tabs are off for lower temps or idle

[terry735001]

I looked through just a couple tables in your tune, there are so many different tables compared to the stock file. For example your WOT Main Spark table is asking for 30 degrees of Timing! WOW. Stock is around 15-18 degrees.

I would suggest taking all of the tables in mine, and pasting to yours just see how it fires up. I would guess your getting so much knock retard that your running mostly in the Low Octane timing table, if that is even enabled still, then the Low Octane table only has 2 degrees less. Not Good. Seeing that much timing in the High Octane table tells me the other tuner didn't really know what he was doing or maybe it's still setup for Propane, I don't know. The changes made seem like "In Theory more timing and less fuel will increase MPG", but in reality you can't run like that. Those values look like something you would run on 115 Octane.

Your Spark Dwell Settings are also 20-30% different.

All of your Idle/RPM/Proportional settings are much different also, like 500% different.

Desired IAC Area Max, huge difference. 2000 vs 226.

MAF Airflow table isnt that far off, a good sign that the overall setup is the same.

Injector Flow Rate vs Manifold pressure also very close to the same but I don't see Injector Flow Rate vs Fuel Pressure.. strange.

Fuel Prime Pulses are 0'd on your tune.

02 sensor Rich/Lean values are lower on yours.


LTFT Min Learn is 200% on mine, 6% on yours.

Closed loop Proportional is Disabled on mine with 0 in my tables, yours enabled and set to 14g/sec.

There's a lot changed, I would try to revert back to stock, sounds to me like Fuel Correction is limited and not showing you the real problems your having.

A big problem I see is with Open Loop F/A vs Coolant Temp vs MAP. Yours is basically set to 1.00, which isnt adding any fuel cold. Set this back to stock from my table.

PE Enrichment, your tune has that running very lean, so very lean with 30deg of timing, not good. Put back to stock (mine).

Transient Fueling is disabled in yours.

Missfire detection, this is disabled around 400-500rpm on yours, likely why your not getting codes.

So many things that arent good in yours, I would take most of my tables and import into yours. You should see big changes.

some how i was posting the same time you where as i see my post after yours
i wish i seen your post before i started working today . would have pulled some stress off of me but still helps now .but some how i got the balls to try to set what tabs i think back to stock

i swapped only the things related to the motor only to stock from a tune file i got from a 2005 8.1l Allison and flashed it to the PCM . next start up did a crank position relearn and reset
now i have a very low misfire count and it seems to be running better but idle still sounds like i have a miss when standing at exhaust pipe and smells more rich
i well add scan / stock file / used and my new tune file here . if you could take a look at my scan and see what else i need to do . i see some RED numbers in the upper right 02 tabs and so i am not sure what i need to do

newRV.2018.hpt
2005 8.1l all5spd stock silverado.hpt
new2.hpl

O the Propane tune was on the PCM that came with the motor and was never used as it was the wrong PCM for my new TCM so the Propane tune was never a part of any of this

as for the guy that made my tune and set it to me is form here http://www.pcmperformance.com/programming.html
in the end i guess this is what cost me a motor in 30K miles and $3k to get to the bottom of

20181111_135854.jpg

[10_SS]

some how i was posting the same time you where as i see my post after yours
i wish i seen your post before i started working today . would have pulled some stress off of me but still helps now .but some how i got the balls to try to set what tabs i think back to stock

i swapped only the things related to the motor only to stock from a tune file i got from a 2005 8.1l Allison and flashed it to the PCM . next start up did a crank position relearn and reset
now i have a very low misfire count and it seems to be running better but idle still sounds like i have a miss when standing at exhaust pipe and smells more rich
i well add scan / stock file / used and my new tune file here . if you could take a look at my scan and see what else i need to do . i see some RED numbers in the upper right 02 tabs and so i am not sure what i need to do

newRV.2018.hpt
2005 8.1l all5spd stock silverado.hpt
new2.hpl

O the Propane tune was on the PCM that came with the motor and was never used as it was the wrong PCM for my new TCM so the Propane tune was never a part of any of this

as for the guy that made my tune and set it to me is form here http://www.pcmperformance.com/programming.html
in the end i guess this is what cost me a motor in 30K miles and $3k to get to the bottom of

20181111_135854.jpg

I'll look closer at the details later, but the key info I would put back to stock are the Open Loop fuel table back to stock to start with, they basically removed the choke by doing that. And turn the missfire detection back on, you will see it, it's the only lines in that table that are maxed out around 300-500rpm. At least you may get what cylinders have missfire.

I dont think they changed much hardware, if any except the cam sensor style and front cover that holds the sensor. I think the cam is the same, injectors, intake, etc. I would put most of the fuel tables back to either my file or the 2005 file you have, as long as you are sure that one is stock. Also put PE fuel back to stock. Spark timing, compare your tables between mine and the 2005 file.. you dont want too much timing, that can destroy your motor. If both files (mine and your 2005 file) have similar spark timing. use ours, seriously.

Putting all the fuel changes back to stock like mine and the 2005 file should do nothing bad, only good. Including the 02 sensors. Just don't floor it but right now I wouldnt floor it anyway.

You could do sections at a time.. or at least a complete tab at a time.

YOur saying you had that mail order tune in there and you think that destroyed the motor? After looking at the tune, basically the spark timing and lean fuel condition, I'm surprised it lasted that long. it had to be knocking all the time. I mean ALL the time. Mine knocked a bit more than I like with 50% less timing than you had in those tables, and your tune basically had the Low Octane table set the same as the high octane table so as the knock was occuring, usually it increments towards the lower timing in the Low Octane table to stop the knock, but there wasnt much difference so probably knock knock knocked itself to pieces.

Most of the time the factory tunes cant even take 1 more degree of timing or it will knock, let alone 15 degrees.

Before I bash that tune too much, I will make sure I was looking at the right tunes.. but I only had 1 8.1L tune, that was mine, and I saw your tune said 8.1L in the settings so what else could it be. lol

BTW Crank Relearn only has to do with Missfire detection, at least from I've read. It doesn't affect the way it runs, pretty sure anyway. Usually only have to do it after putting a new ECU on a different engine it's never been on before, rebuilding, etc.

Also wouldnt worry about the hot fuel in rails, they stopped the return style rails long ago, it's not an issue with the high pressure they run at these days. Maybe a bigger problem when it was lower pressure, not sure.

[terry735001]

..you dont want too much timing, that can destroy your motor...
..you think that destroyed the motor? After looking at the tune, basically the spark timing and lean fuel condition, I'm surprised it lasted that long. it had to be knocking all the time. I mean ALL the time ..

this is what happen at 29K miles . this knocking was funny as you see it under low RPM and under load only



before i really started dumping money into this i did beleave some how the spark timing was off . i emailed the guy that made the tune and asked him about it and sent him the tune file

this was the email i got back
"i am confident it's not the program and i highly doubt it's the PCM hardware. unless of course it got roasted. it's an 87 octane map so the timing is stock almost everywhere. it's may be lean for some unknown reason or other engine related problems."

any ways i cant be mad . this RV is my home and is every thing . if the motor goes down again i could lose my home. the amount of debt i had to take on to save it and my place to stay has me set back for years so if this happens again then every thing is lost .
i dont have the skills for this so i really really need help to get this 100%

i trusted what he said and swapped just about every part i could intell i was only left with the PCM
i now have all most a 90% new motor

10_ss giving you have had a RV i am sure you know what full-timing is and what its like to count on your RV with the wife and kids in it
it was a very good thing i had a friend that had a drive way 400 miles away that i could set in for 6 months why i worked this out
trying to do any work in a RV park is a no no

[10_SS]

That is Spark Knock due to too much timing, no question.

What is happening is tune tune is putting in too much timing right off the bat. Then the knock system is pulling that timing because it hears knock, so it pulls probably 10-15deg of timing, then knock stops. Then the knock stops and the system starts putting all that timing right back in, that part is normal but it's putting back in way too much because the base tables say to put too much in.. The point of the Low Octane Table is as the knock sensors see knock, a multiplier (Knock Learn) starts to increment from 0.00 to 1.00 as it hears knock, with 0.00 = High Octane spark table, and 1.00 = 100% of the Low Octane Table, it quickly starts to use timing from the low octane table which is usually 10-20deg lower than the main High Octane Table for a reason (if I hear continuous knock, I must have "bad gas" so make timing less, for a longer period of time so I dont destroy my pistons and cyl walls, and bearings". You get the point. As fast as it increments from 0.00 to 1.00 (Knock Learn), it may take 2-3x the amount of time to go back to 0.00 (High Octane Spark Table).

I would put my tune in there, 100% all tables, just see how it runs and idles. Keep in mind, the idle circuit is adaptive, so it may not idle great for the first few minutes after you load it since the previously learned values are burned in EEprom, so they will be slowly updated with new values due to the new tune.

Peak Power Tuners as I call them dont really know anything other than find ways to increase timing and lean out fuel. In a vette which is light, they are not under much load most of the time, so that is likely fine. this means cylinder temps dont get that high, so knock may be less. In an RV that weights 4-6x the vette, as you start to load it up from straight minutes running at basically 100% load at what you think is normal throttle ( i have proof of that) then cylinder temps get very high, valve temps get high, and that helps start the spark knock problems you have. You need the stock tune to manage this knock, rich fueling under load helps cool the combustion chamber and stop hot spots that cause knock.. if you stop the knock then cyl temps come down, then you can start to run higher spark timing and regain that lost power/mpg. You may think your cruising down a flat road at say 75kpa (75% load) but could be at 99kpa (99% load) and for maybe 1-2mins your still in CLOSED loop (14.7afr) which is optimal fueling for cruise, but then the ECU switches to PE open loop fueling.. this is because it knows this, and is trying to stop KNOCK from occurring. If you have audible KNOCK like you have, that is equivalent to hammering on your brand new pistons. You can hammer for awhile, even softly, it will take it for a while but will start to change shape, wear cyl walls, then eventually pieces will break off, especially cast aluminum. If you ever ran a two stroke lean under WOT, you will melt the exhaust port side of the piston pretty quick. THis is due to LEAN. While you may make tons of power lean, you will melt stuff. In a 4 stroke, this means knock. I guess until you run both lean and see the damage, then do it 2-3 more times, then finally richen it up and watch all of these problem go away, maybe you wont see the connection.

It is called High Octane and Low Octane just to make sense of why we need temporary loss of "optimal" spark timing, since spark timing is 90% of where the power comes from (other 10 % is from the fuel air ratio). However, with the correct AFR, you can increasing timing to match = more power.

Anyway, what the bad tuners do to get more power and use less gas is advance timing (partly by reducing the knock system sensitivity) and lean out the ARF. Contrary to what most people think, you will not see a drastic loss of power during the fist (inaudible) signs of KNOCK! The loss of power comes directly from the Knock Detection system pulling timing to stop the knock from occurring.

So, if you add 10deg timing to all timing cells and pull out any enrichment (but running enrichment cools the cylinder combustion to stop knock from occurring in the first place) then you net more HP with less fuel used.. but at the cost of a rebuilt every 20k miles.

What some people will tell you is you lose most of the power BEFORE knock is even detected, but that is simply not true. Your only losing noticable power because of the sudden 10deg reduction of timing that the knock system said to pull. By desensitizing the knock system just a bit, it stops pulling timing so it feels SO MUCH MORE POWERFUL but now your banging pistons but you cant hear it so it's fine right. Yes once Knock gets really bad, you lose power fast, exponentially, but not before knock is occurring.



Keep in mind, all these tuners do to get more power out of corvette and camaro v8's, is reduce the knock system sensitivity and lean it out just a bit. That's it! With a cam change you might adjust the fuel injection timing a bit. You would never reducing timing or richen fuel on a stock motor to make more power. Never. Think about that. Reducing Spark Knock Retard is just makes the motor more responsive but increases wear, the big changes come from the transmission torque management... basically stop reducing power between shifts, and instead of limiting power in 1st to 75%, make it 100%, and make the engine Rev higher, etc.

Regarding the RV, that is a really nice RV, and I often thought about doing exactly what you are doing.. taking the family mobile. If I had a nicer unit like you I probably would have. But you have to leave the tune stock since it's a heavy tow vehicle, basically, if you want more response then tune the trans tables... that's where it's at.

I had a 2002 like mentioned, I loved it and because of it the GM 8.1L is the only motor I would run in any coach regardless of manufacture, unfortunately GM discontinued it so now Im left only with Ford Gas v10 which suck, or deisel but WAY to much $$. I may end up buying the last GM 8.1L Workhorse Chassis made.. ever wonder why some RV's are so cheap? They are ALWAYS Ford v10 powered. Pure Junk. Low low end torque, bad MPG, and mechanical problems right out of the gate with the v10. The Workhorse 8.1L chassis out of the gate only had one problem and it wasnt even mechanical.. it was just the cam sensor. That was the "update" everybody talks about in 2004-2005, and it wasnt even a problem but whoever made the sensor stopped making it so no replacement was avail. Anyway, the GM 8.1L Workhorse is always 10-20k more money. Point is you have a good powertrain and investment, so don't give up!

I have since sold our 32' with the GM 8.1L and swiched to trailers and ever since have been looking to go back to Class A, and any of the "good deals" always have the blue oval on the steering wheel. Depressing I tell you. Actually it's not even that it's just because it has a blue oval, it's because that's really the only people selling any that is affordable these days. That's how great eh GM 8.1L is. Knowing all of this I would have kept what we had. We bought it, put 20k on it, had 0 problems, then sold it for the same exact price! Loved that Workhorse.

It's been proven to be a workhorse even though as "marketing" as that sounds that's the name they gave it. That motor is 100% spot on for an RV application no doubt.

I know for a fact these 8.1L motors are indestructible on a stock tune, as long as you change the oil - occasionally. They have been proven to use less gas, produce more torque than the only competition (Ford V10) and just don't die as long as you change the oil (and don't mess with the tune). The early 8.1L's did have a bad cam sensor which they quickly replaced with a newer version and front cover, but that was it. The motor had minimal changes, and none that required a tune change.. just slight optimization due to whatever little changes they decided to make. Sometimes OEMs will make a slight change after 2-3yrs of field testing just to see what real affect it has on emissions, power, reliability, etc. In general rule is if it's less than 5% change of anything, no reporting or re-qualification needs to happen.

Im actually bummed that the aftermarket never came out with headers, cam, and heads for these beasts. It's one hell of an engine. Discontinued unfortunately. I'd say it's one of the best engines ever produced.

You want to run a fully stock tune with than big GM 8.1L. It's a torque monster, ultra reliable, and gets the best MPG any gas RV will ever get, it's been proven time after time, the onnly problme is GM discontinued it for whatever reason, so Workhorse,

If you want more mid to high end power, install headers or a turbo but turbo will ruin your mpg. standard larger ID headers might increase power if your running mid rpms+, but low RPMs, they may hurt. Smaller headers increase low end torque, larger dia. headers increase higher rpm power. There's no way to max everything. As you know, advertising is always about peak HP, Torque. I've learned to ask questions about power at 2000rpm. What happens there compared to stock?

[5FDP]

Raylar did/does make parts but they aren't cheap that's for sure. It just never caught on like the LS stuff because barely any vehicles here fitted with it in the everyday driver world.

http://www.raylarengineering.com/

[10_SS]

Raylar did/does make parts but they aren't cheap that's for sure. It just never caught on like the LS stuff because barely any vehicles here fitted with it in the everyday driver world.

http://www.raylarengineering.com/

That must be new, within the last couple years, thanks for that 5FDP. 100lb ft is decent for $2400 but I doubt it's at the same rpm. If it is, then hats off, that has to drive awesome. That would be a dyno proven Inake/cam/head combo - only way to go. You want increased torque at your normal towing RPM, if more power comes in at higher RPM great that will help pass, but nobody uses HP for towing, don't know why people see these 250k RV's advertise 300hp and get excited... lol. Tell me Torque at what rpm already.

For $13K you can have 500lb ft at 2000rpm. Stock at 2000rpm is around 375lb ft. That's good but the stock setup isn't weak by any means. If your going to invest in the $$ to get the Workhorse to start with, then +13K, then understand you will still get shit for mpg, just spend more get the diesel if you want to tow with your RV. I guess it comes down to if you allready have an 8.1L, towing a vehicle behind the rig or not, through mountains. Yes = diesel. No = stock 8.1 is fine. I do want to drive a standard Chevy 2500 with an 8.1L, just to see how it drives. I bet with the right trans tune, it would feel pretty torque. They come with manual trans? Must have come at a premium, they are rare.

[terry735001]

You should look into the workhorse r26 ufo . its setup like a class A diesel with the motor in the back and not under your feet when driving
I love this setup so much i copied it into my setup . so this is why you see my motor in the back of the RV as a gas pusher
They where last made is 08 09
Before i got my RV it was a diesel pusher but it had a fire and the motor and trans where pulled .

I got the body and chassis for all most free . from a you pull it junk yard and towed it home . this was before the crash of 2008
Back thin i made parade floats for a living and so this kind of work was fun to me and i had the skills for it
So like every 1 else i lost every thing in the crash of 08 and my wife lost her heath so this thing for fun became a life boat
And when shes stuck in bed for most of the day its nice to have a window that moves for some thing new to look out of each day

I tryed to go back stock when doing the RV rebuild but the dealer was all about making money and was not friendly at all for info and parts info
Giving i had no skills on diesel motors and gas was a low cost and not hard to fix on the side of the road then that's what i was left with

I had a 2005 suv that had the 8.1L that i used for work and loved it
I had the skills to do every thing but the PCM .
The guy i was working with know what it was going in and know i wanted stock as much as i could get . he said i could help with MPG and i was like ok sure
I never ran the motor hard as i am all ways good to my stuff
The motor all ways had super HP and got towing 7.5 PMG and 8 not towing . no knocking or tapping sounds
On my last trip we where going to yellowstone and on the way home i had a driveshaft start to go bad
Fixed it and next trip out i would some times put the bed up in the back to see how things are doing when driving as there is no sound at all when the bed it down . cant hear a thing as its 35 feet away
The video was taken next as i was thinking i was about to have a motor come part
I had to drop my driving speed to 55 to stop the knocking and by the time i got home it was down to 45mpr but it made the 400+ miles to get home and this was 6 months ago
All that time i could not find what was wrong with the motor . every tested i could do showed the motor was good .
Handed it off to the shop and they could not find any thing wrong with it
What sucks is for the 8.1L you can find any thing on Measuring Piston to Cylinder Bore Clearance but the shop said it was ok and all Cylinder bores tested good
But 2 of them seemed off to me to the eye so i order the big reman kit that came with new Pistons but the shop wanted me to go back with the old 1s to save money

The only thing and i mane the only thing i cold find wrong when pulling this motor apart was a rocker that looked hammered
Keep in mind when i am asking this that there was no sound at idle no sound a WOT or any RPM no tapping or knocking sound at all intell i have it in gear why under load at low RPM and gave it some gas
So what i would like to ask is if the timing was that fare out could it have been hammering that valve
20180924_104116.jpg 20180924_104135.jpg 20180901_162524.jpg

When you look at the video does it sound like a valve tap to you . guess i am just looking for some kind of piece of mind on what happen

i well look at your tune file and see how it looks to the 05 file . and i did not do any thing to the trans setting

EDIT update

so i made some small errs . good thing i keep looking at youtube videos

when i did the swaps form my tune to the stock i was doing it tab for tab and i was in Basic View vs Advanced View so there where some tabs i was not seeing
there where a hand full in timing and fuel i did not see so this should help .. i hope this helps . have to reflash the pcm

I know the exact volume did vary slightly throughout the production of this engine, created by slight changes to the cylinder head.

when i looked at your tune and the 05 i seen there not the same . so many tabs to look at but i know you had the EGR system and some other things that i dont have
truth be told i have a feeling of what i am doing but really i am just swapping tables and really i am guessing .

[vectorbundle]

There's a lot changed.

there isn't.

the other tuner didn't really know what he was doing

no. i kinda do know what i am doing. you don't know who you are berating and you don't know all the facts.

or maybe it's still setup for Propane

that is actually quite possibly what happened. although i didn't see anything in the RPO codes about it being an alternative fuel vehicle.

i'm just going to mention a few things here. i programmed that ECM+TCM -- 6 YEARS AGO. that particular VIN -- 1GDG5C1EX4F900706 -- was provided to me by the customer. he did his research and gave it to me as the specific RV VIN to use.

the first and main point which is immediately obvious is that i changed very little in the factory file (attached). customer was concerned about fuel economy. i know how to map L18 cals to make power. this wasn't it. all those horrible gawdawful crank-breaking piston-disintegrating +10 degrees flat timing changes and excessively lean AFR that the bad tuners do, because that's all they know -- that didn't happen here.

yeah, the factory cal has some odd values. in retrospect i should have parsed the calibration, i wouldn't have used it. i was mapping several ECMs a day and i was comfortable with the minor relative changes i made to the factory map which i didn't suspect, it was the SPS flash for the VIN provided. now i come across all this ^^^. after mapping literally thousands of ECMs i might overlook something. but if i was a buffoon who "doesn't really know what he is doing" the internet would be littered with hundreds of complaints about me plus i wouldn't be able to do most of what i do to begin with. that wasn't MY idea to use that VIN, it was specifically given to me. that was 6 years ago. i don't just use VINs customers give me anymore, having bricked PCMs for one thing. plus they don't understand what they are giving me and then things don't work. exhibit A. if this was done today, i would assemble my own ECM+TCM cal pair.

the basis for the critique here isn't much different logically. someone going through the file in COMPARE mode (relative to an entirely different cal) while knowingly commenting item by item on every thing that's different, and therefore is bad/wrong, and therefore i changed a lot of things incorrectly, and therefore i didn't really know what i was doing, QED. except i didn't make all those changes. fact is most of them are factory attributes for that VIN cal and i, too, was mainly using it in compare mode to make the minor changes that i did make.

the second point is that there were multiple problems with the vehicle -- not PCM related -- some of which were corrected over time. in fact in the last email it was reported to me that there was no longer engine knock. hm, that's good i thought. all this info in aggregate conditioned the probability further towards remaining problems not being PCM related. some bad smell after it goes into closed and such. well, i didn't touch the fuel. etc.

included were electrical problems, among which it was suspect the PCM may have been damaged electrically. hence the snippet from my email referencing it (probably not) being roasted. i didn't just invent that out of thin air. a replacement PCM was ultimately never ordered. if i mapped a new PCM now -- those new email exchanges were in 2018 -- i would have seen this. as i mentioned in same email, i had idea of some changes i wanted to make (lower the timing below stock + more aggressive PE engagement). so, at that point i would notice some things are off.

but i would know the problem was with the stock map to begin with. and simply changed to a different flash, which for multiple reasons is what you are supposed to do to "go back to stock" instead of copying over all the (visible) differences in compare mode, especially from an entirely different cal. anyway, it didn't work out that way. i'll dig up a CNG or propane L18 medium duty cal and compare the maps, that's probably what happened here. that part is kind of academic at this point. it's obvious what the problem was now and obvious how to correct it. if customer wants he can contact me and i'll email him a new file. i sent him an email. if customer now thinks i am an incompetent moron (after reading the diatribes in this thread who would blame him for thinking that) and doesn't want my help, OK then it is what is.

ironically, over the years i corrected dozens if not hundreds of maps by people who, also ironically, trash other tuners work on the forums. some of which were COMPLETE garbage btw with NO mitigating explanations possible. some of them well known tuners. haven't said anything. customer goes on the forum to trash the other tuner. haven't said anything. maybe i should. tune sucks. this and this and this is wrong. tuner didn't know what he was doing. this is my tune, works much better. the incompetent tuner gets to permanently (i.e., enshrined on the internet) stand in the corner wearing a dunce hat because he sucks and i get to use the opportunity to elevate myself by expounding on how much. i can do this too.

ETA:

so the Propane tune was never a part of any of this

as for the guy that made my tune and set it to me is form here http://www.pcmperformance.com/programming.html
in the end i guess this is what cost me a motor in 30K miles and $3k to get to the bottom of

not this. *that* propane tune was not a part of this but *a* propane tune certainly was, because the attached stock cal for the VIN you gave me to use is, in fact, a propane cal. it took me 1 minute to check that this is in fact a propane cal by comparing it to what i know is another Medium Duty P59 propane cal -- it is THE identical cal with all matching segments. so the person who provided that specific VIN to "the guy" and instructed him to set up the PCM (and TCM) using the calibration for that VIN, which happens to be in fact a propane VIN, is not the one who bears any responsibility? OK, got it.

despite seeing myself maligned for using the calibration for the VIN you instructed me to use, i'll offer you one last bit of advice if you happen to be reading this. do it the right way. it's not complicated. if you continue to play these games of manually copying over values from totally different L18 files (02 k3500, or whathaveyou) into your propane file just because the values look different as a means to "go back to stock", you will have yourself a nice frankenstein propane cal.

there are several reasons why this is NOT a good idea. i won't explain them. whoever understands what they are doing will know what they are. it may work out OK for you... OR it may seem good enough but you may cause yourself other problems which will only become manifest down the line. in which case maybe in another 3 years a post will appear lamenting problems caused because a different "the guy" on some forum parsed your file and fixed it for you by copying over bunch of values. maybe..