Q: My check engine light comes on when I turn on my ac

asked by on September 17, 2017

My car was acting funny and then would not start. I changed the sensor the coil packs sit on then it ran fine. No check engine light,no gas Cap loose light nothing. Soon as I cut my air conditioner on I started having the same problems. What could that be.and when I turn my heat on I get heat on the passenger side but cold air on the driver's side.

My car has 165000 miles.
My car has an automatic transmission.

Check Engine Light is on Inspection $79.99 - $89.99 Get a Quote

Hi Mark. Thanks for contacting us tonight. The check engine light is a generic warning light indicator that will illuminate when an OBD-II trouble code has been triggered and stored in the ECU of your Buick. By having a professional mechanic complete a check engine light inspection, they will be able to download those codes and trace the trouble spot that is causing your AC / heater issues. The problem with cool air on one side and hot air on the other is often caused by a damaged blend door actuator.

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