hello Guys and Gals, i am new to the site but not to the cars, i do have a bit of an issue thought. i have a 2000 monte 3400 with 84K on it. i bought this about a year ago this winter. i have changed plugs/wires/coil packs/fuel filter/air filter/muffler/ battery/tps/idle air valve all just as a precaution this summer. everything was still original equipment. the other day the car would not start unless i pressed on the gas pedal just a tad and hold at 1000rmp, if i let go it stalls. if i do this 2 or 3 times it may stay running barily at 500rpm? i have no check engine light and good fuel pressure. today i have changed the TPS again and the pigtail connector just as a precaution, i've been haunted by one of those stupid pigtails before on GM cars. do you guys have any ideas???

thanks
Luke

 

got 5V at TPS

 

My initial thoughts are:
- Failing fuel pump (but typically it just won't start period).
- Fuel filter (being changed a year ago, it really should not be an issue).
- Fuel line leak (but a leak that bad, you would smell it and see it dumping out).
- Vacuum leak perhaps - if you can get it running, mist starting fluid around the engine and see if there is a spot you spray that the idle changes.
- Fuel pressure regulator (not sure how to diagnose that one).

When it runs, does it sound like a mis-fire?
Lastly, this may sound crazy, but when you changed the plugs, what brand? If you say BOSCH, rip them right out and get some AC Delco or NGK plugs.

 

hello Jason, thanks for the tips, i have found the issue though. my temp control switch is bad. while testing the pigtail i had 5/12V solid i started the car and it ran like normal. i have owned dozens of chevy's and all seem to have had TPS sensor issues or wiring or temp control switch issues or wire issues. amazing how a 10$ part can cause havoc on the entire system. i unplugged the temp switch and it fired right up, but now my fans are staying on. has anyone figured out how to get that temp switch out without cutting that motor puller bracket off that gm thought it be a good idea to put right in the way!!!!