The air conditioner on my 94 accord is causing the engine to stall when at idle.

After about five minutes with the a/c on, there is a knock inside the evaporator case. As soon as I hear the knock, the rpm's drop for a second or two and then there is another knock and the rpm's return to normal idle.

It does this several times before it stalls the engine and only with the a/c on. I can rev the engine so it won't stall, but I don't want to ruin the compressor.

Any idea what's going on here? What could be knocking in the evaporator case?

 

Is your a/c cooling properly? Open the hood and see if the knocking noise is related to the clutch engagement of the a/c compressor.


Sorry, didnt notice the date on the post.