okay well i just finished doing my valves and timing everything is fine expect one thing, and thats my idle it only does it when the car is sitting there in N dosnet do it when driving or anything else.

car will sit there and RPMS will drop to below 100 and the car will almost stall out then it will jump back up to 800-1000 RPMS and just keeps doing that so i dont know what it could be if u guys have any info that would be of great help

 

IACV, and check for a vacuum leak.

 

Check your IAC vale by looking under the intake manifold (if you have a 94 LS) and there should be a connecter there. If you can unplug it with the engine running. What happens is the engine idles at a very low rpm and the check engine light should come on don't worry about the light. However, if this does'nt occur have the IAC valve replaced. Finally regarding the CEL after re-plugging the connector it should come right off, if not try resetting it by disconnecting the negative terminal from the battery, have your radio security code on hand before doing so. And please only do this if you're capable of doing so cuz I'm not responsible for any mishap.