Q: Car lurches when AC is on

asked by on July 10, 2017

When stopped at a stop light, or in traffic, my AC blows air warmer than what is outside unless the outside temperature is below 78. When accelerating, the cars RPM will go up as the air compressor turns on. When stopped it is also turning on and off at about three seconds apart. The lurching never stops as long as the AC is on and it struggles to push out actual cold air. As soon as I turn the AC off, the lurching goes away. I'm just wondering what the issue might be because it's too hot in Florida to go without AC.

Also, below I accidentally selected that my car has a manual transmission, it has an automatic. I misclicked when filling the information out.

My car has 155000 miles.
My car has a manual transmission.

Hi there. When the engine is put under a load by the AC system, the car’s computer automatically attempts to compensate for that by adjusting the idle. If there is carbon buildup within any part of the system, including the idle air control valve, throttle body, or possibly even the EGR valve, it can cause surging. It would be a good idea to have a professional mechanic come to your location and complete a car surging when AC is on inspection before your trip, so they can isolate the source of this problem and recommend the right repairs.

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