Discussion in 'Chevy Trucks' started by sdplowing, Feb 17, 2008.

  1. sdplowing

    sdplowing Senior Member
    Messages: 108

    Coming back from D&D's this morning and truck loses power. I figure fuel gelled, it was only 10 degrees but I had just got fuel from a less than reputable station. Pull off filter, while still in pj's, pour in some diesel 911, put some in tank, prime it and it starts right up and the check engine light came on. I let it idle for a while then put it in gear but when ever I gave it any more than very light throttle it would lose power again. So I idled my way 1 mile home with the truck blowing quite a bit of smoke. Got home, put it in park and reved the engine to see if it would cut out again. It didn't, but it wouldn't rev over 2000 rpm and still smoked white.:realmad: Anybody have any ideas? Hopefully I'm having it towed to the dealers tommorow. BTW it's a 2004 chevy 2500 Dmax allison 55000 miles.
  2. William B.

    William B. Addict
    from S.E. IA
    Messages: 1,027

    Sounds like the truck is in limp mode. To clear that, disconnect the batteries for a little bit. What kind of smoke, blue or black? It could also be the connectors for the injector on the number 2 and 7 cylinders. Here is a link on how to fix it.

    If neither of those work check the injector harness along the alternator bracket. Some times the the wires will rub through there and short out. is a good site for GM diesels so do some reading over there.
  3. yamaguy

    yamaguy Senior Member
    Messages: 555

    One of our guys had that problem last year. Make sure to replace the fuel filter with a new one. That is the only thing that would help him. He went through three filters that tank and then never went back to that gas station again. The D-maxes seem to be more sensitive than the PSD's.
  4. OP

    sdplowing Senior Member
    Messages: 108

    William B. Thanks for the info. I cleared the limp mode, pulled the connectors and squirted in some dialectic grease, the harness checked out ok. It was blowing a white/blue smoke before, but it's warming up now with no smoke. I'll take it out for a test run in a few min. Thanks again for your help.:drinkup::salute:
  5. William B.

    William B. Addict
    from S.E. IA
    Messages: 1,027

    Not a prob Sean.
  6. dirtyedge

    dirtyedge Junior Member
    from se WI
    Messages: 12

    Instead of clearing the codes by disconnecting the batteries you can just cycle the key three times and it will disable the limp mode. This will allow you to test drive the truck and see if it happens again.

    You should take the truck in and see what the code is, this will tell you what is going on with the truck. If you know anyone with a programmer it should be able to read the DTC. If not you can take it to Autozone and they will read it for free.

    I invested in a Actron scanner a few years ago and it has been a life saver many of times. Not only can you read the codes but you can clear them as well.

    As someone earlier stated if you have any questions with you dmax take a look at dieselplace as there is a never ending supply of information.

    Hope this helps
  7. vegaman04

    vegaman04 Senior Member
    Messages: 372


    ive read that you should change the fuel filter every other oil change on the duramax's