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Q: When I turn my AC, my car shuts down.

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My AC works, it cools down the car, the problem is that: I notice when car is in "P" (But it does it in every shift) shift, with my AC on, I flood my car and it accelerate good but when I release the pedal the motor sounds like it will shut down with no power (when I have the AC off it doesn't happen) The AC compressor is a Universal one, and has a single relay outside the relay box, its holded near the fan, and a cable goes from the battery to the relay than to the button, than to the compressor, It wasn't me who made that, I bought the car like that. So today I was in a downhill and I turn the AC on and inmedietly the car shut down, it has happen to me like 5 times, only when the AC is on. I also noticed that tha car vibrate a lot more when the AC is on. The point is that when I turn the AC the car either shut down or the motor loses like "power" to the point that look like its going to shut down. The AC doesn't have any rare sound, it just make the car vibrate a lot. ERICK

My car has 166708 miles.
My car has an automatic transmission.

Hi Erick. It sounds like the idle is not being adjusted/compensated for the additional load of the ac compressor. Additional loads on the engine require the idle to increase to make sure the engine does not stall under the load. What sounds like is occurring is that there is no increase in idle to compensate for the load and is stalling the engine. I suggest having a qualified technician perform an inspection of the idle control system to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a rough idle inspection.

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