my car idle's fine when i turn it on and let it warm up in the morning...and when i get out of school. im not sure what its idling at cuz i dont have a tach.

...but if i start to get on it and rev it a little bit higher while im cruisin and then slow down and push the clutch in or go to neutral, the revs start to pulsate up and down. i have no idea what would could be causing it. if i turn the car off while its doing it and then start it up again it goes away.

...i also did an ecu check, and there is nothing...just a code 17 which is my vss that isnt hooked up...

the engine is a obd0 b18a1 in a 91 hatch.

 

no help....!??!?!

 

Here's some help I had the same exact problem. Idle surges. Check the Iacv on the back of your intake manifold I replaced mine hasn't came back since and also you might want to clean out your fast idle. It's right below your throttle body