Knocking when AC is on.

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09-20-2018, 01:24 PM

Chris2670

Junior Member

Thread Starter

Join Date: Sep 2018

Posts: 1

Knocking when AC is on.

So when I am idling with the AC on, there is a loud knocking noise. It only happens with AC on, when AC is turned off it goes away. If I push in the clutch the knocking stops. Any ideas on what this could be?

12-10-2018, 02:19 PM

Peter09tC

Junior Member

Join Date: Dec 2018

Posts: 1

This is just a normal occurrence, the engine is working harder with the ac/defroster, i have the same thing with my 2009 tC, just don't hit the gas hard with the AC on, that will cause more damage.