I was wondering if anyone could help me? My 1990 when warm Idles at between 500 and 600 rpm. Then if i drive it any length of time it bounces up and down between 600 and 900 rpm. any help would be appreciated.

 

bump

 

bump

 

Try using the idle adjust and idle mixture screws. Check the FAQ or the FSM for it. it needs to be ~750.

Also get something flammable in aerosol form and spray here and there around the motor in quick bursts. If the idle starts to raise when you are spraying in one spot, then you have a vacuum leak. Use common sense and don't spray the exhaust.

 

if the idle is bouncing, your TPS is out of spec. Check www.fc3spro.com for ways to adjust it.

and BTW, no bumps in the second gen section.

 

I have the same problem, i start my car, and i have to help it adjust and idle. Once its idling and at normal operating temperature i adjust the Air Adjust valve ontop of the engine. But everyday i come back and start my car and i have to keep adjusting it to keep it at 750+- 25..

My car dies soemtimes also if i dont let her warm up long enuff and i takee her out the rpm just falls flat to 0..

Ima check out the links ya put up

Jason NYC

 

Or, as stated above, a vacuum leak. Mine still bounces after TPS reset (the TPS is not bad). I just haven't had the energy to replace my lines, as I am going bare block soon anyway.