Quick Question.

When I pull up to a red light with air conditioner on, the car vibrates alot thru the steering wheel and even feel it in my seats.

WHen I turn it off, it seems ok. Even when I put car in Park, it seems fine...only happens when I have the car in drive with my foot on the brake.

Can anyone shed some light on what is going on and what to do?

K.

 

when you hit the "Auto" button or engage the "A/C" button (either one depending on if you have auto or regular climate control), when you hear the a/c compressor kick on, your idle RPMs should kick up about 150-200 rpms (in neutral this would be around 850-900, assuming your idle is set to factory specs of 650-700 in neutral on an automatic...nissan has no specs on idle in drive/reverse so that can vary). if your rpms dont kick up, there is something fishy with your iacv-aac. also, if they dont kick up, there was a TSB about a possibility that one of the wires in the main harness (the one that passes over the engine) could be broken, thus not allowing for the a/c idle up response. Try turning on your a/c in park, going under the hood, and shaking some of the wires while a friend sits in the car watching the tach. you could also have your friend sit there in drive, with his/her foot on the brake while you do the same thing. if you jiggle the wires and the idle shifts up and down then you know its the broken wire. otherwise, do a search to diagnose the iacv-aac valve (need a voltmeter). good luck.

 

The same idle problem happens to my max except i've noticed this happens with the headlights on. I'll have to check if the a/c does this also. I'll bet your idle drops to around 525 rpm. I didn't know that this might be a broken wire problem. Thanks stillen_i30, I'll have to check that.
I have cleaned the TB and changed the PCV and this problem still persists. My next guess is to check and/or clean the IACV but I haven't found the time to do so.