Ok... Car is a 91 sedan w/ a OBD0 B16. FITV valve was recently fixed, IACV seems to be operating properly because my idle isn't erratic. So here's whats happening.

Whenever the weather has been breaking above the 50 degree mark, it seems like something gets thrown way off. When i start the car and the cars temp is still cold, the high idle that comes naturally at start up is also accompanied with small hiccups (almost sounds like fuel). Also, when i'm driving in a gear and the throttle is closed, when the motor is still cold it bucks kinda violently.

When the car gets up to temp, the problem lessens, but is still felt through the steering wheel and gas pedal when decelerating.

Also, when its cold out (it was 28 when i got in my car this morning) it also doesn't happen...

So what do you guys think? I'm hoping its something stupid like a MAP sensor or something, any ideas? Thanks

 

bump cause it might be a moisture related problem... or just intermittent.

 

I have now noticed my gas mileage has gone to absolute ****... i'm gonna do a pressure drop test on the injectors to see if thats the culprit.... maybe try to test the o2 sensor as well.... I hate obd0 cause i don't even have a check engine light

and yes the light works