ill drive my car normally..and itll get 2 the normal temps and all...so say i go into a store for 20mins.. when i come back itll start but itll barely run..sounds like its gotta mean cam or something. lol. sounds like its not getting enough gas. it sounds like its back fireing if i give it gas 2. itll surge from 500 rpm then itll go up a little 2 like a grand or so..go a little higher..then itll go away. the car does idle a little rough after all this like..even after ive driven it for a wile..i did plugs and wires, replaced entire exhaust exept for y pipe and manifolds. u know how theres a ninth injector when its cold? well..when its warmed up its not gonna use that..perhaps i have a weak injector..or its clogged?? i might try a fuel rail flush at work.....this totally baffles me because i coulda sworn it was my cat. i replaced that along with my old exhaust...so....got any ideas? fuel pump? cap and rotor still need 2 be replaced...could that be it?

ps...my dad said o2 sensor? possibility? im a mechanic but..eh..im stumped!

 

Inspect or replace the cap and rotor (just to make sure the system is reliable). Then consider the possibility of injector or regulator leakage after shutdown. You can test that with a fuel pressure guage on the Schrader fitting after shutdown. If the pressure drops quickly, you may have a leaker.

 

im definitly replacing that soon. at work i did a fuel rail flush. it runs alot better but...it still fluxuates its rpms at 1st when started. from 500-1500. it goes back and forth. is there a way to test the iac valve? keep in mine ive got an 85 tpi..its a little older and i know they changed in 87 or so..

 

After it sits and you start it, does it fire right away, then not idle well? Or does it taken a lot of cranks to start it?

 

well before i did the flush yesturday anytime it was warm id start it and itd barely idle...if i gave it gas either a belt would squeel or it would stumble and it would "bang". it sounded like it was coming from the back of the engine or exhaust. thats why i always thought it was my cat. it would smell terrible and it would rattle all over..but i re did my whole exhaust its new. since i did that fuel rail flush its been ok...but i we'll see what happens

 

Fuel Injectors leaking down.

 

I think it's CTS sensor gone .