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Q: car vibrating at idle

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When I'm driving my car, it feels fine. However, when I come to a stop, it starts shuddering. Having the AC on seems to make it worse. It feels like the car is dying and starting again. One of my friends thinks the car might be losing air when its idling. What do you think might cause this?

Since the AC compressor is driven off the engine crankshaft, turning the AC on puts more of load on the engine. This often intensifies any underlying engine performance problems.

I think your friend is referring to a vacuum leak, which could indeed be the cause. However, there are numerous potential causes for your concern.

The first step is to check for diagnostic trouble codes (DTCs) stored in the car’s onboard control module. These codes serve as a starting point for any further diagnostics.

I suggest you have a professional, such as one from YourMechanic, diagnose any DTCs you may have, and repair your vehicle.

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