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Q: Air conditioner causing car to overheat

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My air conditioner causes my engine temperature to go up. When the air is off, the temperature is fine.

We need to determine if your vehicle is actually overheating, or if the gage is just reading incorrectly. If your vehicle is overheating; you will no doubt have boil over from the radiator or reservoir. The fact that your gage spikes up so rapidly when A/C is selected leads me to believe that there is an electrical issue somewhere.

Perhaps the coolant temp switch is mistakenly plugged into an A/C pressure switch. You need to find a qualified technician in your area familiar with engine electronics to get to the root cause. YourMechanic has qualified technicians that can help you diagnose your overheating issue.

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