Strange Noise

could be this maybe


SPECIAL SERVICE MESSAGES
15697 NORMAL CONDITION: MOMENTARY GRUNTING SOUND
SOME VEHICLES WITH AIR CONDITIONING UTILIZING R-134A MAY EXHIBIT A MOMENTARY GRUNT/POP AFTER BEING PARKED FOR SOME TIME & THE COMPRESSOR IS ENGAGED BEFORE THE ENGINE COMPARTMENT HAS WARMED UP. THIS IS DUE TO LIQUID R134A BEING PUMPED OUT OF THE COMPRESSOR. R134A WILL TRAVEL TO THE COOLEST POINT (THE COMPRESSOR) ONCE THE ENGINE HAS COOLED, DUE TO THE DIFFERENCE IN TEMP BETWEEN THE ENGINE COMPARTMENT & THE VEHICLE INTERIOR. WHILE MANY VEHICLES HAVE PCM STRATEGIES THAT ADDRESS THIS BY REPEATEDLY CYCLING THE COMPRESSOR ON START- UP, THIS MAY NOT TOTALLY ELIMINATE IT. REPLACING A/C COMPONENTS WILL NOT ELIMINATE THIS. COMPONENT DURABILITY IS NOT AFFECTED. MINIMIZE THE NOISE BY TURNING THE A/C SYSTEM TO VENT BEFORE EXITING, & IN MILD AMBIENT TEMPS (APPROX. 50-75F) WAITING A FEW MINUTES BEFORE TURNING ON THE A/C OR DEFROST.
EFFECTIVE DATE: 03/06/2002

nope, not a grunt - a sneeze... it is your AC I don't care if you don't have it on. I was in denial as well

Actually if your heating config is set for windshield/feet - your AC is on - whether the manual AC is hit or not. This is the car's way of defogging the window - which is what you selected.

Try it - try either of the windshield positions on the hetating switch have a listen. Try any other position have a listen... try again with AC button on.

If you open your hood - listen for the sound. If you are standing in front of the car looking into the engine area, look in front of the passenger headlight, near the ground. There is in fact a solenoid kicking a pulley wheel in and out of the belt path. And the sneeze happens right when it jumps.

Cheers.
P

also if you notice when you put your defroster on the ac light is on

My compressor is making this noise every few seconds with the AC on while driving... its really annoying, anyone find out if there is a way to fix it or am I stuck with it!

creedog said:

I have this noise you guys are talking about. I have been worried as well. What the heck is going on? Is this hissing/clicking every 10 secs going to be a normal sound? I just started to hear it this week, especially when the A/C is on. I looked down in this exact area and saw it spin and stop, spin and stop, so on and on. Has anyone been to the dealer (aka service dept) to ask if this is normal. If so I'll deal w/ it, but I would like to know if I have a problem on my hands. Any updates would be very helpful.

Click to expand...

This your ac cycling its the liquid gas in the system making the noise. trust me, im a refrigeration man as well as a mechanic. Maybe that sound is from your blow off valve from you supercharger. Oh, no wait thats mine.