My idle used to surge up and down, but I took off the IAVC which was making a loud humming noise, found nothing wrong, switch the coolant line to allow better flow, it stopped surging the idle, but still hums loudly. Any suggestions?

 

Nobody know? ****. Maybe it'll blow up or something so i can replace everything again, till then screw it, just drive...

 

somebody asked me if I had taken off the lid to make sure everything was tight. The bottom piece that bolts on with the coolant lines going to it doesnt have anything inside of it, it just allows coolant to flow through to cool it off. The screw on the side of it was taken off and the spring is fine, cant get to anything else. Put back together and had to adjust it to idle properly again, still humms...help

 

What engine is it. B16a's have FITV problems and you just remove that and screw back in the plastic thing that holds a spring in it. Also your IACV could be dirty just use some throttle body cleaner and spray it in the IACV. You could also have low voltage going to it, check it with a voltmeter.

 

Its a D16A6 that I dropped into a 90 CRX DX and did the dpfi to mpfi conversion on it. I dont have a multimeter, only a voltage tester (lights-up a fuse). I blew it out with an air compressor.