Runs good tell turn on AC to highest setting then check engine light flashes and motor shake noticed the tensioner was loser then I thank it should be other then that everything looks ok does over heat when setting but one fan is out I know that
My car has an automatic transmission.
The flashing Check Engine Light means the engine is misfiring, which can be very harmful to your catalytic converter. If it starts doing this when the A/C is turned on, then there could be a problem with the ignition system being unable to handle the increased load placed on the engine at idle. This could be as simple as worn spark plugs or a weak ignition coil, but it could be more serious like low fuel pressure or low compression in one cylinder.
The overheating is also a problem, but most likely a separate one entirely. I would strongly recommend having the ignition system checked by a qualified professional, as well as having the overheating issue diagnosed as well. Consider YourMechanic if you decide to get this fixed, as a certified technician can come to you and perform these checks on your vehicle.
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