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'02 2500 reduced engine power

K

Klueless

New Member
Joined
Nov 23, 2015
Messages
5
Hey all,
figured I'd try here to see if anyone has had/knows about these symptoms my '02 2500 started having. 

A few weeks ago I was driving along with cruise on, and suddenly it started slowing down and wouldn't accept any throttle input (drive by wire system on this one), it also popped several backfire/coughing noises at random intervals.  I coasted to the shoulder, and turned it off (it didn't die on it's own).  Then it wouldn't start until I'd let it sit for like 20 minutes, at which point it started, but ran very high idle and the throttle pedal was dead.  Zero codes (!!!!).  Idled home, parked it overnight, and the next morning same high idle, but now a reduced engine power message and also a code popped saying the TPS was the issue.  Replaced that, and everything was fine for 2 days, then it all happened again.  Took it to the dealer, who after diagnosing everything said the whole throttle body was bad and needed replaced, so I did that and it worked for 3 days...until this morning. Same symptoms as above, except this time around it DID die on the shoulder, and no amount of waiting will get the thing to start.  It cranks and fires like normal, runs for literally not a full second, then dies.  Every time.  Worst part?  Zero codes, zero CEL.  Code reader thinks everything's cool.  Towed home and now trying to figure out what to fix.

Has anyone ran across anything like this?  Thanks in advance ~ Jake

TLDR:  Replaced parts codes and dealer had an issue with, now 3 days later same symptoms and zero codes. 

 
Have you ever run it out of gas, or really low on gas a bunch of times?
If you have, I'd throw a fuel filter at it if it hasn't been changed (probably needs one anyway)....and if you are still having problems, do a fuel pressure and volume test. If that fails, drop the tank, and check the fuel pump. I've had the strainer on the pump clog up solid. No joke.
Good luck, and let us know what you find.

CarMech1969
 
If your fuel pressure is good, there is a little module called the
Throttle Actuator Control TAC that will cause you problem like that.

http://www.chevyavalanchefanclub.com/cafcna/index.php/topic,75809.0.html
 
Thanks for the suggestions, I'll be checking both tomorrow and see where she stands (sits?)!

thanks ~Jake
 
Klueless said:
Hey all,
figured I'd try here to see if anyone has had/knows about these symptoms my '02 2500 started having.  

A few weeks ago I was driving along with cruise on, and suddenly it started slowing down and wouldn't accept any throttle input (drive by wire system on this one), it also popped several backfire/coughing noises at random intervals.  I coasted to the shoulder, and turned it off (it didn't die on it's own).  Then it wouldn't start until I'd let it sit for like 20 minutes, at which point it started, but ran very high idle and the throttle pedal was dead.  Zero codes (!!!!).  Idled home, parked it overnight, and the next morning same high idle, but now a reduced engine power message and also a code popped saying the TPS was the issue.  Replaced that, and everything was fine for 2 days, then it all happened again.  Took it to the dealer, who after diagnosing everything said the whole throttle body was bad and needed replaced, so I did that and it worked for 3 days...until this morning. Same symptoms as above, except this time around it DID die on the shoulder, and no amount of waiting will get the thing to start.  It cranks and fires like normal, runs for literally not a full second, then dies.  Every time.  Worst part?  Zero codes, zero CEL.  Code reader thinks everything's cool.  Towed home and now trying to figure out what to fix.

Has anyone ran across anything like this?  Thanks in advance ~ Jake

TLDR:  Replaced parts codes and dealer had an issue with, now 3 days later same symptoms and zero codes.  
Click to expand...

The codes point us in the general direction of the problem, but sometimes the components are still ok.

That generation of truck was notorious for sub-standard wiring in the general area of the throttle body.

Could see replacing TPS might disturb the wiring enough for the engine to run OK for a few days.  May be in need of some exploratory surgery into the looms.  You're looking for loose or corroded pins & terminals.  Suspect grounds.  Frayed & bare wiring, etc.
 
Could also be the Dreaded CPS (Crank Position Sensor)... Sometimes will not set a CEL and go into reduced power mode..
 
CarMech1969 said:
That thread rocks. Thanks for sharing, Nick!  :B:

CarMech1969
Click to expand...

No problem.

Plan on placing the '08 in dry dock for a few weeks, next year.  Will be addressing several issues that can be corrected or improved upon, utilizing alternative medicine.

Making a list, & checking it twice.
 
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