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DTC P0253, P0370 with Mod PCM, no DTC with Stock PCM

L

Last Chance

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Location
Anchorage, Alaska
Hello Truck Stop, I am having some issues with my 6.5 TD and thought I might pick your minds. I have included detailed issues to the bottom of the checklist. Any suggestions would be appreciated.

Thanks Chance

Problem: Explain your problem in concise language
Mod PCM gives DTC P0183, p0251, P0370, fish bites and no cold starts. Stock PCM shows no DTC’s and operates fine.

Demographics: tell us about your truck and your ambient conditions:

- Year: 1998
- Truck model and class (ie: c2500) K2500
- Automatic or Standard Auto 4l80E
- Mileage: (indicate miles or km) 38,000 miles
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) New Diesel Depot Motor, New Standadyne IP, Heath PMD, Heath PCM, HO Marine Injectors
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? “F” Turbo
- Ambient outside temp: (indicate *C or *F) F
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) #1
- What fuel additives are you using? SAE 30
- Where are you located? Alaska
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter K/N Magnum CAI New
- Fuel filter New
- CDR Valve? Cleaned
- Coolant – last flushed/replaced at Within the last year
- Oil – synthetic/regular, changed at Royal Purple 15/40
- Batteries – state of charge, (matched set) replaced at Matched Optima Red tops 2008
- Battery cables and grounds (removed, cleaned and tightened): Cleaned as per TS
- Glow Plugs - how many miles on them? 50 miles___ What type? Duraterms
- Injectors - last changed at _Motor install 38,000_


History: (Describe how the problem first appeared.)
- What were you doing when it happened? Bought this truck as is, Ordered a Heath PCM and troubles began, Bill is diligently working with me as we speak.
- How was the truck running fine before this problem appeared? Truck running a little sluggish, Hard Cold starts, R&R GP’s, 15 mpg, 0-60 18 sec_
- Has this problem ever happened before? _No
- Describe any related factors that might be part of the problem. This VIN# on this truck is an orphan to GMC, Bill had to do some research to supply PCM._
- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) _Y___ And? P0183,P0251,P0370 with Heath PCM, no codes with the stock PCM


Diagnostics:

1] Starting:
1a] Does the engine start? Yes
1b] Does the engine crank over? ________
1c] Are your batteries fully charged? yes
1d] Have you removed, cleaned, and tightened all battery connections? Yes
1e] Does your Wait to Start light come on for a time? How long? @10 sec
1f] Does your glow plug light come on? _________ For how long? _________
1g] Do you see smoke from the exhaust while cranking? What color? I use to see white smoke with a rough idle for 2 minutes on cold start, Thanks to AK Diesel Driver we set the TDCO from +2.02 to -1.94. Starts like a dream now with now smoke or rough idle
1h] Does the Service Engine Light Glow during Start/bulb check? No stock, yes Heath pcm_

2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? ____________
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? _________
2c] Loosen the inlet line from the IP – is fuel coming out (Lift Pump on)? ___________
2d] Loosen an injector line and crank the engine - does fuel come out? _________
2e] Do you hear a vacuum (hiss) when you remove the fuel cap? ___________

3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) Heath mounted on skid plate
3b] Condition of Extension harness (if used) Vendor or Homemade? Heath
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. Good
3d] PMD Make: Heath
3e] PMD Age: 6 days

4] Stalling Issues
4a] Do you experience stalling only when hot? No, fish bites with mod pcm from 2900 rpm up.
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) no
4c] Does pouring cool water over the IP seem to help with restarting? _NA
4d] Is stalling momentary (engine recovers)? ___na______
4e] Does SES light come on when engine hiccups? ___na______
4f] Does cruise control quit working when engine hiccups? __na_________
4g] Does re-starting seem to reset engine, restoring cruise and power? _na________
4h] Changes to dash lights or instruments during stalling events? ___no________

5] Running Issues
5a] On cold start, does upper rad hose get hard before engine warms up? __No
5b] Any bubbles or oil film in coolant overflow tank? ___no
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? _no
5d] Excessive white smoke from exhaust on cold start? _Not anymore_
5e] Excessive black smoke from exhaust under hard acceleration? __none________
6] Performance Issues
6a] Do you have gauges (boost, EGT) ? _No TBinstalled next week.
6b] Maximum boost under load? __Turbo Master set to 2 ½”
6c] Have you added a performance PCM (reflash) or Chip? Yes / NO
6d] Have you changed exhaust / downpipe / crossover? Yes all
6e] Wastegate – mechanical or vacuum (OEM)? Turbo MAster

7] Temperature-related Issues:
7a] Single or dual thermostats? Duals
7b] Have you replaced them lately? Manufacturer of replacements? No, New with Motor
7c] Have you pulled and cleaned Radiator and coolers lately? Yes with new motor
7d] Have you replaced the fan clutch? Manufacturer of replacement? Yes
7e] (winter) Have you tested your antifreeze? Good to what temp? -50
7f] (winter) Are you using a winter grille cover? Yes

List and describe any other factors which are not addressed in this checklist.
I bought this truck with the new motor (from Diesel Depot), the P.O. was meticulous and built this truck to show case his new business of the Cummins CC oil cleaner machine, I assume he soon found out that these IP’s don’t like this mix. The IP was replaced in 2008 with a new standadyne IP.
I owned a 94 2500 suburban three years ago, sure seems to me that it ran a lot better than this one. This one seems a little “fat”, hard to get her moving, lot of gas pedal to get it motivated. My neighbor is around diesels all day long, about two weeks ago he stated that my truck does not smell like a diesel while running, long story short, I was running a mix, smelled and felt like stove oil. Pumped out fuel and replaced with #1 and 6 oz of ATF on first tank. Truck seems to be running somewhat better now on second tank with no additive. Next will have sae 30.
With all the mods done to the truck all it was lacking was a PCM so I ordered one, 5 weeks ago. While ordering through Bill I was told that this VIN# is an Orphan and was going to take some time to research. The first PCM was C-N-S. The second PCM would start with a 1/3rd throttle, drive test was responsive but with hard shift, really hard shifts, then it would fish bite at the above mentioned RPM’s. This PCM would not start cold, only if the swap was done at operating temp. DTC’s P0183,P0251, P0370.The third pcm is a ditto of the second. The DTC’s are not occurring with the stock PCM.
Last night Les aka AK diesel driver met me and we set the TDCO from +2.02 to -1.94. We then swapped to the MOD pcm and we could not see any TDCO values, same start symptoms’ as before. Back to the Stock PCM for the drive home (10 miles).
This morning it was 28F, the truck cracked right of with minimal smoke.
It should be noted that Bill Heath has and still is working with / supporting me on this issue, only thought there might be some ideas to try to minimize Bills time?

Chance
 
Don't use ATF. Use sae NON Detergent 30wt or 2 stroke oil. I can't help on the tuning but it sounds like your truck and the computer vins dont match. I think TurbineDoc was having this problem just trying different (random) pcms in his truck
 
Thanks for the input. The ATF was a one shot deal to help clean from the mix fuel scenario, don't plan on using it again. I was told to maybe look towards the CPS or OS?
 
Why is this Vin# a so called "Orphan"? (Although I don't doubt Bill in the least, just never heard of this before).....Whats the story.....1 off, special order?
 
Well as I understand it when you request a PCM program and give him your VIN, he has a VIN database for all vehicles made with all pertinent information need for the program. I personally cant go into great detail as its beyond me, but when My VIN was not in his database that he uses for programming, he referred to it as an Orphan. I have owned this truck for 7 weeks now so I don't know about any special issues from PO's?
 
When we put in the GL4 from Bill I noticed that it took quite a bit of cranking to get it to start and that was at full operating temp. It immediately coded and when I tried to clear them the CEL flickered but wouldn't go out. It almost seemed like it was starting in limp mode but after it started it didn't necessarily display all the symptoms of limp mode. It's like the ECM isn't registering either the CPS or maybe the OS. I'm hoping maybe buddy or Kojo can chime in here.
 
He should be able to use any program from a 1998 truck. It might be that your truck is not actually a 1998. Did you check the build date on the door jam sticker? Its a month and date in one of the corners. I guess the VIN# may also contain a date code. Check the build date on the door though, maybe it was like a 97 crossover which would need a different definition file.

All your codes are like saying your Optical Sensor (OS) isnt even plugged in, which maybe the file isnt reading from the right inputs, I'm not sure.

You didnt fill out the LP diagnostic, those are important for fishbiting, so does the timing, so if you havent run the Modded PCM with the timing set right now then it will be way different. I cannot believe the last guy didnt time it right. One thing I would check is the idle fuel rate, is should be near 8mm3, and if its real low like 0-2mm3, some PCM parameters could make it work worse I suppose.

I am surprised it would take more than a couple PCMs to get it right though.

Every time you swap out a PCM you have to run the timing procedure, because its saved in the PCM, so when you put the Heath PCM in you need to run the TDCO Learn, either on the scanner or with the KOKO. Now if you ran it with the stock PCM and took it out and put in the Heath PCM and ran the timing then both would be up to date and could be interchanged without running the timing TDCO Learn. But anytime you get a different PCM or change the IP or CPS or timing chain you need to run the TDCO Learn. If you didnt then that might be part of the issue. And then there is that whole security passlock procedure thing you have to get right.
 
IIRC he put in a new LP from Bill too and measured the volume output but I don't think he put a guage on it. I believe he took care of the passlock my understanding is that if the passlock isn't taken care of it won't start at all. The odometer was rolled back before he got it and it makes me wonder if someone tampered with the vin. Is there anyway to read from the ECM to know what year it's tuned for?
 
On OBD1 scanners you get a Scan ID, or a PCM Calibration ID, or PCM Cal ID (those are each the same thing). I am not sure if you get one for the OBD2 PCMs.
 
Buddy,

#1.)Door jam build date is 09/97. One would think that the VIN would reflect this?


#2.) Lp is new, it passed the flow rate test of 1 gallon at 2 minutes idle with 6 turns on cockpit. Fuel gauge test 6psi at idle, 3-4 psi at cruise, 1 psi at wot. New hose from FFM with new Filter. I am ordering the OBD 2 scanner this week so I cant check the fuel rate and time.

#3). I can't run the TDCO relearn on the Heath PCM with the active DTC's that I am getting with that PCM?
Passlock reset works with the new PCM's.

AK Diesel;
The odometer was rolled back which would make one a little concerned, but after talking to the PO and his intention of use of this rig with all the work that was done would explain why.

The PO is a wealthy car enthusiast. He bought a "Cummins cleaner" that recycles Crank case oil and mix for burning in this rig. Before he started selling/ marketing the "Cummins" device he built up a "new" old rig to help his marketing sales pitch.

The local GM dealership shows this VIN with a broke crank, last log entry in 2007. So the PO bought this rig cheap and put in the new motor, degrease d the engine room and painted, installed new firewall insulation, new moog front end, replaced the oil cooler lines with custom steel braided hosing, new P/S pump with custom hose, new gear box, new Master cylinder and Controller, along with rebuilt tranny and transfer case. He wanted the truck to be new and with that in mind he paid to have the odometer rolled to zero to reflect the build.
I have verified the VIN against the VIN located on the passenger back frame, they match.
I spoke with Bill yesterday and he states that he has a new PCM headed my way, I guess I will have to wait and see.

My only concern with the truck is if it is running right stock or not? When the engine was rebulit they reused the old IP (125K miles on it), a new IP was bought and installed in 2008. The big question is did the PO used the "Cummins" mix with the new IP and if so would that have messed with the new IP /OS?

The stock PCM was sent to Heath to read and verify...
 
buddy said:
He should be able to use any program from a 1998 truck. It might be that your truck is not actually a 1998. Did you check the build date on the door jam sticker? Its a month and date in one of the corners. I guess the VIN# may also contain a date code. Check the build date on the door though, maybe it was like a 97 crossover which would need a different definition file.

.
Click to expand...

Not always case Buddy, sometimes it works as a direct swap other times it doesn't I've had successes & fails both, apparently when they went to OBD-II many more definition files in a given year up to 58 variants ? So it may start and run it doesn't always run well, Passlock is another variable that has to be learned as well
 
Last Chance said:
Buddy,

#1.)Door jam build date is 09/97. One would think that the VIN would reflect this? Should, but if somebody swapped PCMs from another vehicle then it wouldn't be correct, some folks assume one PCM works in another vehicle straight up, that is not always the case


#2.) I am ordering the OBD 2 scanner this week so I cant check the fuel rate and time. Which one ?

#3). I can't run the TDCO relearn on the Heath PCM with the active DTC's that I am getting with that PCM?
Passlock reset works with the new PCM's. A cheap code reader can clear the codes and you can do the 30 minute ko/ko cycle to learn the theft code



The local GM dealership shows this VIN with a broke crank, last log entry in 2007. So the PO bought this rig cheap and put in the new motor, degrease d the engine room and painted, installed new firewall insulation, new moog front end, replaced the oil cooler lines with custom steel braided hosing, new P/S pump with custom hose, new gear box, new Master cylinder and Controller, along with rebuilt tranny and transfer case. He wanted the truck to be new and with that in mind he paid to have the odometer rolled to zero to reflect the build.
I have verified the VIN against the VIN located on the passenger back frame, they match.
I spoke with Bill yesterday and he states that he has a new PCM headed my way, I guess I will have to wait and see.

My only concern with the truck is if it is running right stock or not? When the engine was rebulit they reused the old IP (125K miles on it), a new IP was bought and installed in 2008. The big question is did the PO used the "Cummins" mix with the new IP and if so would that have messed with the new IP /OS? IP/OS should not have been impacted by this, other than opacity, the optic sensor has to be able to "see" the disc through the fuel if it isn't any darker than red fuel it should be okay, being recycled oil as part of the fuel I suspect it may be dark or possibly created a varnish on disc maybe making it hard for encoder to read the disc, but lets see what happens with the PCM flashed to your VIN 1st



The stock PCM was sent to Heath to read and verify...
Click to expand...

see comments TD
 
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Turbine Doc said:
Not always case Buddy, sometimes it works as a direct swap other times it doesn't I've had successes & fails both, apparently when they went to OBD-II many more definition files in a given year up to 58 variants ? So it may start and run it doesn't always run well, Passlock is another variable that has to be learned as well
Click to expand...

Very true.

OBDII has several VDF's for each year.

I've tuned a couple OBDII trucks locally that I've had to write complete custom VDF's for just to get in. That was a nightmare.....

It goes by VIN, and even then there's differences.

There's half year VDF's, l65, l56, and a couple other variables. That's not even taking into account differences like gearing, etc.

Heck, my 98 alone has 4 possible VDF's.

I've dropped in a several stock PCM's in my 98.

A 2000 L65 PCM and it ran fine, a 99 l65 PCM and it ran but like crap, plugged in another 98 L65 and it barely ran at all.

Flashed each with my 98 stock cal file and it's all "hunky dorey".

Get the wrong one and it runs like crap, if at all.

Now, that's with my tuning software, I'm not sure what Heath is using. I'm guessing he uses a tech II and since he does it as a business, I would think he would be more than aware of such differences.

Probably just a bit of a mess up.

I'm betting the new PCM Heath has on the way will fix your issue.

Everybody seems to think tuning on of these old hoss's is straight forward.

Not by a long shot. These dinosaurs are probably some of the most challenging pieces of kit to tune I've run across yet.

OBDII 6.5 even more of a challenge.

I would say it's probably like this because they are a kind of "half step" between the previous gen mechanical injection and the next gen full on computer controlled DI diesels.

Something like the old computerized carburetors were when they transitioned from carb to FI.

What a nightmare those were to work on. It was like they took the worst of both gens and stuck 'em together. Don't even get me started on Ford's variable venturi setup. In fact, scratch the computer carb/nightmare comment....those variable venturi carbs are probably the worst nightmare ever conceived for a delivery system, ever. Oddly enough, it's a very similar design to slide carbs that have been used on motorcycles with great success. Go figure....:dunno:

Right now, I'm considering getting a "T-series" PCM from Heath.

Too bad I can't read the cal on a PCM. My software just won't pull it off the flash chip and I haven't been able to figure out how to get it to read.

Lyndon says it's locked out by design (can't download others custom tunes) and John over at TC says it's a limitation of the OBDII flash chip (IE: flash but no read). Meh, whatever.

Either way, it seems to be just outside my home schoolin' programmin' edumacation!

;)
 
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I think the problem is that perhaps you have a 1997 PCM, since it was built in September of 1997 and October may have been a parts cutover. Thats why the Scan ID may be a better indication. back in the day they didnt always release models in the really early quarters of the previous year.
 
So an update on this thread, recently Chance lost his engine. Starting to look/sound like a main bearing went out.
 
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