1995 Honda Accord a/c makes weird clunkety noise

Texas summers are brutal. That being said, my 1995 Accord V-6 (188K miles) acts like Jack Benny’s Maxwell when the a/c compressor is on. Periodically it will kick the engine into a low idle (when stopped, not when moving) which makes it go “whirrr-clunk” rhythmically. My mechanic, who is a certified Honda guru, says that the V-6 engines on the 95 Accord just seem to do this when it’s really, really hot outside, and he’s been unable to find a fix for it. It’s about to drive me nuts.



Any ideas?



Thanks, in advance –

The “whirr-clunk” sound you describe could be nothing more than the idle momentarily increasing (whirr) to compensate for the added load of the compressor, and the clutch engaging the compressor (clunk).

You could always take it for a second opinion, but if this is a trusted mechanic and he’s got a good rep, it might simply be the nature of the beast. Some cars just make noises when they do certain things, particularly once they get to be 14 years old with almost 200K on the clock.

Have your mechanic check the expansion valve operation by using a set of manifold gauges. The expansion valve is what contols the pressures from the continuously rotating compressor. Unlike with a Cycling Clutch Orifice Tube system where a pressure switch controls the compressor pressure. ff the expansion fails to go to the proper position for the refrigerant line temperature, it can cause the compressor to over-compress the refrigerant gas into a liquid. This is called slugging the compressor. And it will make that whir-clunk sound.

Tester