Hello, I am new to hummer, I have a 2007 Hummer H3, and I noticed today that when i turn the air conditioning on, the car idle harder and shakes. not normal! what can cause this problem? also i hear like cranking sound from the front passenger side on idle as well, and when i give it a little gas it goes away and then it come back on idle, and most likely this happen when the AC is on.. what this might be??

thanks a lot

 

That is the AC Compressor running, and contrary to your belief, that is normal for an I5.

Same thing happens when the Alternator responds to a heavy load and has to boost output to demand. You are detecting the load put on the belt when the AC Clutch kicks in.

 

Oh so that shake is normal? What about he clicking noise that coming from the front passenger side?? Is that normal too ?

 

Open the hood, start the motor with the AC off. Have a friend turn on the AC after a couple minute warm up and watch & listen to what happens.

 

So what I should be looking for when I am doing that?

 

You're looking/listening for the clicking. It is likely the A/C kicking on & off. Your freon could be a bit low, so the A/C will click off at idle, back on as RPMs increase.

 

ok i will check tomorrow since its crazy raining today

 

i found out that there was something lose was hitting on the intake box and causing this noise. thanks for all u guys help