95 S-10 won't idle, smells like flooding

[rknorr]

95 S-10 4.3 TBI: problem started suddenly at startup yesterday. Truck is hard to start and will only continue running if you keep the revs over 1000 rpm. The truck sounds like a funny car at idle. No previous problems like this, no recent changes, as a matter of fact I drove the truck 50 miles and parked it the night before without any trouble at all. If I unplug either fuel injector the truck actually runs better. I believe the TBI is dumping lots of gas into the intake, I just don't know why it is doing it. Only one change I can think of, the temperature has dropped 20 degrees. HELP!!!!!

[maxwedge]

Scan it and see if the coolant temp sensor readings are stuck on a low temp even warmed up, common problem, for starters. Post back results.

[BlazerLT]

1.) Do a tuneup.

2.) Get it timed with the brown and black timing wire unattached from the PCM under the glove box.

Bet you it needs both.

[rknorr]

Thanks for the ideas. I will try them early next week when I'm off work and will post results.

[rknorr]

Its fixed. I checked the cap, rotor, wires, MAP sensor, replaced the EGR line that was cracked, checked the ignition timing all to no avail. I discovered that the problem was self-induced; I installed an aftermarket tachometer a while back and neglected to insulate the wire where it ran through the firewall. That wire was apparently grounding out the tach terminal even though the tach was working. Once I insulated the wire where it goes through the firewall, the problem disappeared. Thanks for the help - Ray

[BlazerLT]

interesting.

[rknorr]

My problem has returned, definitely was not related to the tachometer. I have removed the tach and problem is still here. I just replaced the engine coolant temp sensor, was no help. Quick review of symptoms: 95 s-10 4.3 TBI - Z engine code. Will only start if holding accelerator down some otherwise will start and die. Won't run under 1000 rpm, sounds like a top-fueler the way it misses and lopes at idle. Problem had been intermittent but has come back solid the past week. While running the injectors are dumping loads of gas into the intake, will actually run better if I unplug one of the injectors. I am getting no codes and the truck is undriveable. What do yall think about the EGR being stuck open? I have it out right now and the pintle is about 1/8" from being closed. I would expect it to be almost completely closed. Any help appreciated. HELP!!!

[BlazerLT]

EGR valve stuck open.

[rknorr]

Yup, you're right. The EGR was stuck open and only $190 for a replacement too! Truck runs fine now. Funny, I never got a service engine light the whole time the truck wouldn't run. Thanks for everyone's input - Ray