well im having a very annoying problem on my 88 rx7, when i start the car its just fine warming up but when it hits idle it just sits at 1000 rpms and surges to about maby at most 1200rpms and and back down to 1000. i looked for vacuum leaks but cant find any , i adjusted the TPS and still no luck. sometimes when its all warmed up and i slightly but my foot on the throttle it will stablize but it wont drop from 1000rpms. also it has a very hard time cruising under 45mph, when i try to hold it at like 30mph it will flutter a bit then do a slight acceleration and it does this over and over again, can anybody help?