Volvo RWD 700 Forum

INDEX FOR 1/2026(CURRENT) INDEX FOR 9/2011 700 INDEX

[<<]  [>>]


 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

Weird IAC problem update, any ideas ? 700 1985

John,

OK thanks, now I understand how the IAC motor works. That explains why the door flops open and closed so easily when it is removed. I can check the duty cycle and signal with an o-scope, but I don't think that is what the problem is. I just checked the engine timing and it is around 11 degrees at idle with the a/c on or off (750 or 900 RPM). The thing I can't figure out is why the engine RPM drops so much when the a/c clutch releases. Apparently the ECU tries to compensate which would explain why it surges to about 1500 right after the dip in RPM. Then it goes back to normal. I have checked the throttle switch adjustment, but I will go ahead and trace the signal down to be sure it is working correctly. I don't suppose the clutch could be temporarily binding as it is released ? It is working fine when engaged, and I am getting 40-42 degree air.

Thanks,

R Duke






THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD

New Weird IAC problem update, any ideas ? [700][1985]
posted by  rduke  on Sat May 1 05:23 CST 2004 >


<< < > >>



©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.