i have a d16y7 civic 96 and the idle is fine when the car's A/C is off but when you turn it on and you are a stop light, the idle shakes the whole car at about 650 idle. then the idle goes up and then back down. Then you turn it off and then it goes back to normal. Does anyone know what might be causing this problem?

 

It may be the ide speed control valve.

 

what does the a/c have to do with it though?

 

now my civic's compressor doesn't grab when turned on but the fan for the condensor turns on. could it be a bad compressor?

 

the idle speep c.v will adjust rpm when load is put on engine. AC, rear defrost whatever. Also could be map sensor.Does both fans kick on when you turn ac on? Your compressor may just have a bad relay, not turning it on. I dont know where it is located on a civic though.

 

yes, both fans turn on. before when both the compressor and the fan turned on the car shook realy bad and had a low idle. now the compressor itself won't turn.