I bought a '96 chevy 2500 pickup a couple of weeks ago - I knew it needed a 4L80
transmission and I just got that installed two days ago.
But when I started the truck, the engine starting
bucking and surging like crazy, with a lot of black smoke when I give it the throttle.
It sometimes idles down a little better but any touch on the accelerator revs the engine
to about 3500 - sometimes it wants to "stick" there even when I let off on the pedal.
The truck starts up fine and quickly every time.
I dont have a scan tool and I do have an SES light. I tried driving it like this but the throttle
acted so weird with jerky accel / decl that I didnt want to tear up my just installed transmission.
I know this truck has a fly-by-wire accelerator pedal. could that pot be flaky?
I have done a little reading and it seems that there are a lot of problems
with the injection pump - I hope thats not what I'm needin'.... Anyone got any ideas/suggestions?

 

Theres not a lot of problems with the injection pump just the pmd. You could have a pump laying down but I suspect you have something more along the lines of a ecm going out.

 

Thanks for your quick reply - I also have an 88 diesel suburban 6.2L and a diesel Escort
and a 7.3 van...
so being an old-timer I like the mechanical injection diesels better...
What should my next step be - putting a scan tool on it?
Do the accelerator "pedals" go bad?
As in the voltage output spiking around? Would the scan tool tell me the output of the accelerator pedal?
Also I have heard of many people mounting the PMD away from the engine
This probably would help if the module werent already bad, huh?
Thanks again for your input(s). I would really like to be able to use this truck.

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I also have an 88 diesel suburban 6.2L and a diesel Escort
and a 7.3 van...
So being an old-timer I like the mechanical injection diesels better...
What should my next step be - putting a scan tool on it?
Do the accelerator "pedals" go bad?
As in the voltage output spiking around? Would the scan tool tell me the output of the accelerator pedal?
Also I have heard of many people mounting the PMD away from the engine
This probably would help if the module werent already bad, huh?
Thanks again for your input(s). I would really like to be able to use this truck.

Read more: https://www.dieselbombers.com/diesel...#ixzz0oDvAtVvH

Thanks richardsonsf

 

pedals going out are pretty rare. there was a suspected bad pedal on another site but it turned out to be another bad pmd. yeah pmd needs to be mounted outside engine. mine is on the inside of the bumper. im thinking your injection pump is dying though. but getting the codes would be a good help though

 

Thats of course not what I wanted to hea,r woody35, but i guess i was kinda expectin' it...
I am going to check the codes tomorrow thanks again!
richardsonsf

 

i dont know what your budget is but if you want to try a new pmd first that is what i would do. pmdcable.com is a good place for it. thats where mine is from. a pmd is a helluva lot cheaper than a injection pump and if your going to keep this truck your going to have to get a new pmd anyways.

 

Thats the problem it could be a pump, pmd, pedal, or something in the ecm and none of them are cheap.