Q: Car chugs when AC is on at a stoplight - 2005 Chrysler PT Cruiser

asked by on November 29, 2016

When I have my AC on and I am stopped at a light or cross road for several seconds the car starts to chug and shimmy. It stops as soon as I turn off the AC

My car has 54000 miles.
My car has an automatic transmission.

Car idle is rough Inspection $94.99 - $114.99 Get a Quote

Hello - there may be a problem with your idle air control valve. Its job is to bump up engine idle when there is an additional load on the engine, such as the AC compressor. Other possibilities include a dirty throttle body, air leak in the intake, or other problem causing a rough engine idle. I would recommend an engine inspection of these systems by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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