Injector help asap

[pimajim]

Really upset. I was just finishing a 400 mile trip and my 2001 GMC Duramax went into the LIMP mode. I was towing a 6000 lb trailer, and just coming off the interstate. I have 115000 on the truck, It was running great except I was thinking it was getting a little noise, just did a oil change and general check over, old oil did not have fuel, truck does not smoke. I drained the fuel filter, truck started and got me a few more miles to the campground. Next day replaced the fuel filter, did some local non towing drives, all was great.
Headed home, 200 miles down the road it stopped again, limp mode..pulled oveer, let it cool some, ran again, short time later did it again..found out if I had the heater on full blast it continued to run (it was 90F out) However only gauge that showed anything was the transmission temp.
Bring it to a dealer, I truly do not like, hour later he says injectors are bad. Warranty ran out in FEB on them. He wants about $5000 to fix. I wonder if they are bad, he refuses to give me the trouble codes. I guess because I did not buy the truck from him. Talking with GM customer service, with GM's problems I don't think they will help.
At a loss now, sr. guy here, 165 miles from next GMC dealer, looks like truck will have to go as no$$$ to fix it.
And still don't have a warm feeling the injectors are the problem. any comments appreciated
Jim in Pima AZ 33N 110W

[Dek Hawkins]

Hi Pimajim
I own a 2002 2500HD Duramax. I have had the Injector problem and have replaced them all BUT I live in England, (NO WARRANTY) so it cost me OVER £4500 , (work that one out in Dollars).
Dont think your problem is Injectors, when mine failed there was no fault code showing as it is not programmed to spot it, PLUS it should not run again after a cool down. I think your dealer is after a nice earner.
Mine went into limp home mode when the Transmission Switch failed.

Dek Hawkins

[Mark Rinker]

Injector problems rarely set a limp. If you are not smoking, knocking, or making oil - have them clear the codes, apply 2002 or later programming, with all latest updates for the LB7, and get the hell out of there. The fact that they won't share codes with you is very suspect. They are basically telling you that you aren't smart enough for the truth.

My guess is that you are setting an overboost code while towing. 2001 ECM programming had a problem with this, and will limp for no reason. If its never been corrected, this is the likely culprit.


Are you running any kind of programmer or custom tune? Boost valve or fooler?

What were your water temps when the limp was set? Transmission temps?

[pimajim]

Thanks for the input.
When the truck went into limp mode, the water temp was normal, and the transmission was a little warm (200F) But outside temp was 90F I have never had a upgrade that I know of.
Where to next????

[kaylabryn]

If it runs fine without the trailer, and your trailer is a bumper pull!! I could come get your trailer and you could bring your truck up to Brown and Brown in Mesa. They have always been straight with me, though I have only used them 3 times have heard lots of good things. Like you said you are about 140 miles from here.

Mike

[Mark Rinker]

Thanks for the input.
When the truck went into limp mode, the water temp was normal, and the transmission was a little warm (200F) But outside temp was 90F I have never had a upgrade that I know of.
Where to next????

Theres not much wrong with your truck. Get to a good dealership.

[pimajim]

GM called me back yesterday, warranty on injectors ran out couple months ago, so they will not touch it. They said local dealer told them that I have excessive fuel return to the tank.
But I cannot seem to correlate that with Limp Mode and a heat related thing.
Another dumb question, before the trip I changed the oil, and added STP as it seemed alittle noisey..could this have affected anything???
Really appreciate any help

[Mark Rinker]

Where are you now? If still at original dealership, have you asked them to clear the codes and asked for your truck back yet?

Not aware of any STP diesel oil additive. What oil did you use?

If the truck was 'noisy' that could be a fuel knock, created by excess fuel dumped into a cylinder by a failed injector. However, there is almost always CLOUDS of exhaust smoke associated with a severe fuel knock.

Something is missing here...has the dealership given you the codes that were set? How about the cylinder(s) that have high fuel return rates?

[pimajim]

Hi again
STP is a slick additive, have used it for 100 years, friend always used in in his diesel.
Dealer, we have parted company, did not buy from him, and I wonder if he is one of the 3000 GM announced today is getting a pink slip.
Yup, no smoke..even took it out and really cranked up the RPM for a bit, no smoke, plenty of pep, mileage has not changed, just did a power wash of radiators including fuel cooler. We have constant dust storms
Talking to a fellow in Phoenix, does race trucks, says he can wring it out if I like. So will see when he can see me. So will see what happens.

[Mark Rinker]

Did they clear your codes, or do you still have an SES light set?

My advice would be to call JK at KennedyDiesel.com and talk to him about getting upgraded to a custom tow/economy tune based on 2002 programming. The fact that you were towing when the limp occurred has me guessing that you had the 'phantom overboost code' that John will tell you all about.