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horsecamper
01-08-2008, 13:18
“Whitey”, 2001 2500 HD Duramax with Allison, 4X4 Extended Cab Long Bed. Stock. 65,000 miles.

Anybody have this kind of experience with this engine/fuel system?

Duramaster, could you please also respond. “Whitey” will be going to DSU in Phoenix for all repairs and I thought that I’d get some opinions prior to taking him in.

Current problem is that the truck is kicking an SES and is going into limp mode when towing, or on start up after being used for towing. I don’t have the common symptoms of cracked injectors: No obvious diesel in the oil, no white smoke or any smoke at all, no rough idle, no hard start either cold or hot. The truck seems to have good power and fuel consumption. The transmission has never given me a problem.

History-Bought last March. Previous owner is a friend. The friend mainly used this truck as a daily driver. The truck never kicked an SES with him. He didn’t use any fuel treatment, but bought good fuel. The historical warranty information was that both the injection pump and the transmission have been replaced, but not the injectors.

As soon as I got it, I started using LUCAS fuel treatment (8 oz. per tank) and started towing with it. Noticed a very random infrequent hesitation at approximately 65 mph with steady driving. Had this both towing and not towing. Had I only been towing, I would have thought that it was just the trailer hitting a bit of a bump and making the truck jerk a bit. Never kicked an SES in approximately 2000 miles. Just as a precaution, after 1000 miles, I took it in and got the fuel filter replaced. This made no change.

All summer long this truck was hooked to the trailer (app 10,000 lbs) and I towed with it in the mountains. It no longer has that bit of a hesitation, but I’ve kicked an SES a few times as follows:

Ist Incident-I had towed several long fairly steep grades with it with no problem. After camping, I started it up and let it warm up prior to leaving. When I got it to go I had an SES. It was downhill and all of the gauges looked OK, so I started out. The truck went into limp mode for a couple of minutes and then went out of it. The SES stayed on. I drove into a town, unhitched the trailer and took the truck to a Chevy dealer. The service service invoice says that I had a P1226 and P1229 code. The service invoice also says that diagnosis was performed and that the PCM was intermittently causing concerns with injector control. The technician said that PCM failures are very rare. A new PCM was installed (part cost $1,500) and reprogrammed. I traveled home with no further incident.

2nd Incident-While towing, not on a grade or recently on a grade, I had an SES. I was close to the camp site, so I kept on driving. When I started the truck up to go home, the SES was still on. I drove almost home, picked up some fuel, and when I started up, I had no SES. I later took the truck to the local Chevy dealer to read the code. I told them about the new PCM. They said that they fix stuff in a particular order for that code. This second service invoice (different dealer) did not list the DTC. The service invoice says that a 220 diagnosis was performed and found that the flow chart indicates a Fuel Injector Control Module problem, #2 and #3 injectors. The service guy recommended that the FICM (part cost $800-900) be replaced. Then he said that if that didn’t work, it had to be the injectors. This rig is not under warranty, so I decided that I’d just drive it a while and see if it would get worse.

3rd Incident-I let the truck sit a couple of weeks and then started it up and left it to warm up. When I went back to pull the trailer out, I had an SES and it limped. I unhitched it and pulled out and then reversed it. I’m not sure what reverse normally does when it limps, but I had no reverse. It was just like neutral. Also, the normal clunk that you get with full power when you shift from part to reverse was not present. I turned it off and started it up a couple of days later and it ran normally, no SES.

4th Incident-Hitched it up to a lighter trailer and did a bit of hauling, let it sit a week, unhitched it, went to start it up and it kicked an SES. It limped, and again, it didn’t have reverse. Turned it on and off a couple of times and the SES went out and the truck acted normally.

The only thing that the three of these incidents have in common that I know of is that, just prior to turning off the engine, I would have been pulling a heavy load up a bumpy gravel grade really slowly (3-5 mph) in four wheel drive high. (Maybe high, possibly low)

This SES is not consistent. I have hauled a good sized heavy hay trailer several loads up slow gravel grades (4 wheel drive low) and did not have an SES.

I have been driving the truck with out a trailer for the last few weeks and can’t get an SES out of it. “Whitey” runs like a rat up a rafter, tears up the tires.

I want to get this problem fixed, but I have a bit of a problem going through a whole bunch of expensive repairs for the thing that is NOT causing the problem. I have read in some forum that the 2001 standard programmed ECM does not like to tow, but if it is reprogrammed with the 2002 programming it is a happy little towing machine. Does anybody know anything about this? I would hate to spend a fortune on “Whitey” and find out that it was the 2001 ECM programming. How conclusive are these DTC’s ?

Please comment. I’m a novice and am not too familiar with this PCM, ECM, FICM stuff. I don’t have a code reader, but am willing to take it in again and get the last code read, or to buy a code reader and learn how to use it.

Mark Rinker
01-08-2008, 14:37
I do not recall the codes set, but my 2001 was not code-free until I upgraded to the 2002 programming. My dealer did it.

Personally, that would be my first step if it wasn't already done with the ECM swap.

horsecamper
01-10-2008, 10:56
Thank you Mark. I'll call up the dealer and ask about the programming. If it wasn't done, I'll get it done.

horsecamper
01-10-2008, 11:36
Mark, I called the dealership who replaced the PCM and talked to a service guy about reprogramming the ECM. He gave me the standard line about reasons for leaving the thing stock. I asked him if 2002 programming would cause an issue and I don't think that he knew, so I got the run around again. Did the dealership do yours? If I remember correctly, I read about somebody else getting 2002 ECM programming for their 2001 ECM and the delaership did it. I think that the cost was $500-$600. Who reprogrammed your ECM and what did it cost? Thanks, Horsecamper