Engine/Transmission (1998.5 - 2002) I have a problem

[Qualey]

Just got off the interstate after cruising at 75 for an hour. Shifted from 5-6 and felt something that I thought was an outside wheel banging a curb. Turns out it was a pulse as the accelerator went dead. Engine runs OK, but check engine light is on and no response from the acc. pedal now. I guess the truck is teaching me a lesson for test-driving the Duramax's.



Any obvious things I am missing?

 

[MPlunkett]

I am definately not the expert here, but the dead acc pedal is usually symptomatic of the VP44 going bad... ... I hope its something else... ... Good luck

 

[Joe Mc]

I guess the truck is teaching me a lesson for test-driving the Duramax's.

Any obvious things I am missing?

Don't drive any more maxipads . . .

 

[Supermod56]

Read the codes, more than likely it's a VP issue. 0216 is the code for a kaput VP44 if I remember correctly. Cycle the key from off to the on position 3 times, and leave it in the on position the 3rd time, and the check engine light will flash the code(s).



Tom

 

[Qualey]

Thank you

I'll go check the codes right now. As luck would have it its sitting in the Chevy dealers lot. Can't give them the satisfaction after I told them I was keeping the truck for another 100k!

 

[Supermod56]

No problem, Duramax's/PSD's exist for us to have somebody to pass



Tom

 

[Qualey]

Ok



I got codes P1693 and P0121. Truck started and ran fine. Also responds from acc. pedal input. These codes sound familiar?

 

[ACoyle]

Here are the codes that you are looking for.



P0121 (M) TPS Voltage Does Not Agree With

MAP

TPS signal does not correlate to MAP sensor signal.



P1693 (M) DTC Detected in Companion Module A fault has been generated in the companion engine

control module.



For future reference - TMTT has graciously put all the codes in the FAQ for 24V engine & Trans



Looks like the MAP sensor or the TPS flaked a bit. Maybe the truck went into limp mode and now sees everything as OK now.



Suggestion - Remove battery cables - Clean them - Wait half an hour or so. Put them on. - Get in - Turn the key to on. - Slowly fully depress and release the accelerator pedal. - Turn the truck off and start it. If you are OK have a great day.



AC

 

[mhenon]

ACoyle, good advice. If that doesn't work it's probably a cooked APPS or something.

Like all computers (these trucks are computer driven ya know) they get confused sometimes. Turn the darn thing off. . then boot it up and all's well.

Another thing you can do is check all your grounds. I usually go around the truck once a year and pull every electrical connector and ground wire and clean it up. Dielectric (sp?) grease on the connectors and metal-metal contact on the grounds.

Keeps the little computer brain happy!

Mike

 

[Qualey]

Well, I guess it fixed itself. The check engine light is off and it runs and drives fine. I'm going to check the fuel pressure Tuesday just to be safe, but I think I got lucky. Thanks for all the help.



Matt