[smallfry55]

2000 focus 2.0 every time i turn on front window defrost and come to a stop the ingine hesitates big time .this only happens with the front defrost all other setting no hesitation why ???

 

[FociZX4ST]

Your defrost uses your AC...this is hard on an older engine. How many miles?

 

[bluefront]

Well in that position, the AC compressor is turned on. And the idle speed should be raised slightly....by the AIC valve (idle speed control). If that valve is not working for some reason, the engine won't speed up when the compressor is on.

Sometimes cleaning it out w/carb cleaner will get it working again.

Course I'm just guessing here.....

 

[smallfry55]

155,thousand km
what if i unplug the ac will this help coming into winter i diont need it ??

 

[nilskje]

Yes you can unplug, the AC should not start if the outdoor temp is below 4 C (somewhat 37F) anyway.