02 envoy cranks but no fire [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: 02 envoy cranks but no fire

03-15-2012, 02:05 PM
Ok this is my first post on this site and I would first like to thank everyone, this site has helped me many times, i have searched for my issue and I have not come across any solutions so maybe this is something new.

So I have a 2002 Envoy SLT with 114,000 miles, 9 months ago i had the ignition switch replaced, fuel pump filter and injectors and spark plugs, and T Stat, Anyway fast forward to now I have NO CHECK ENGINE light on no errors, and this problem is only interment, My temp gauge dies OUT while driving or when i go to start it it will not move, i have heat and the coolant is warm, At times it fluctuates from 100-200 back to 100 and moves up and down sometimes as much as my tac. however now when i go to start the car it will crank but wont fire. I can get it to start if i completely floor the gas, its still cranks a few times but not right up and other times nothing at all. I have cleaned the TB the only thing that has not been replaced was the temp sending unit, Im completely lost as to what this could be i have left the battery unhooked hoping to clear the PCM but, this problem comes and goes sometimes starts right up no issues others it could take 20 min, and i noticed the times the TEMP gauge doesn't move, the engine wont Fire,

COULD the temperature sending unit be bad and trying to compensate for the "COLD" coolant temp and burning the engine rich because once it starts, it burns off all the fuel.


03-15-2012, 03:05 PM
Even if the cel light hasnot come on, did you have some do a scan with a high end scanner, there could be a stored code that can help. Try to unplug battery foe 1/2 hour to 45 min, replug and see if anything changes, run some good injector cleaner through with a tfull tank of premium fuel 91+ octain.

03-15-2012, 03:43 PM
Thanks for the advice. I have tried pulling the battery. And once it does start it pours out black smoke for a second then idles at 1700 for about a min then goes down to 600 and runs fine besides temp gauge not working.