View Full Version : Rolling idle with AC and blow off noise

07-31-2007, 08:31 AM
Now with my AC in operation I'm back to the old rolling idle game. With AC off idle is good. With AC on idle is good when cold but starts to roll up and down when warm most of the time. It seems to behave worse as temperature increases. Along with this scenerio and I'm sure unrelated, I have an odd sound upon takeoff. Sounds like a added a BOV as I get a pssst accompanied with a momentary hesitation or loss off power. WTF!

07-31-2007, 12:20 PM
you know, its really funny because my ac does the same thing... my idle never has a problem... except when the ac is on and its hot out... it wants to like die at idle and it jumps constantly.. i dont know aobut the bov sound tho haha

08-01-2007, 08:05 AM
Somebody has got to know why an idle rolls when AC is on. [headbang]

Now the psssssssst sound I get from the passenger side engine compartment has gotten longer. Again, only when takeoff end of 1st gear change. A long psssst accompanied with a loss of boost or power or [confused]. Could it be a bad 710N diverter?

08-01-2007, 10:00 AM
Power loss with the AC on is normal. The sound is probably just the ac compressor thing, or the related belt. You should hear the noise my car makes. It makes it through 1st and 2nd.

08-01-2007, 10:12 AM
compressor might be on its way out - causing more resistance so it slows the engine a bit and possibly makes the belt slip, then the idle air bypass valve opens and the engine revs, rinse and repeat.

08-02-2007, 08:08 AM
Looks like it might be the compressor belt being a little loose. This doesn't explain the rolling idle. I guess I'm back looking for vacuum leaks.

Anyone know of a good vacuum pressure gauge for checking leaks?