hey i have a 93 eg hatch and when i put the a/c on (dosnt blow cold) the motor starts to rev up and down right now i have a d16y7 (converted to obd1) and i have NO CEL's what could this be?

(sometimes it does it when a/c off aswell but not as lound and bad)

 

Night Bump!!!! (need to know)

 

Usually the ecu kicks up the rpms when you put on the ac to balance the drag from the pulley. Is it running abnormaly other wise?

 

I re-read your post. What kind of noise is it making. I need more info to try and diagnose the prob.

 

um when the car is stoped but on its fine but when i turn the a/c on the car just strts to rev up and down and its not the idle casue ive checked that

 

It might be a bad pulley bearing. If i could look at/touch it i could tell ya more. Maybe take into a shop and have them do a free inspection then replace needed parts yourself.

 

Probably a vacuum leak. Check all your lines and if you still cannot find the problem, unplug the IACV and adjust your idle to 450rpm and plug it back in.

The A/C probably doesn't blow cold because there is no refrigerant in it. Does the compressor make a "clack" sound when you press the AC button?

 

no the ac makes no noise only the rev

 

If your compressor does not come on like it should when you press the AC button, your idle will increase, since the compressor puts a load on the engine, it will sustain a boosted idle as long as the compressor is running. This could be an increase anywhere from 200 to 500rpm until it turns off, and then a normal idle (750ish rpm) is maintained.

 

thnx for all the info the problem was the idler pulley