Q: My car's Check Engine Light and EPC dash lights are on. And shakes in idle after driving through a flooded street.

asked by on January 23, 2017

I'm in Southern California and we started getting some good rain storms and this morning the streets in my neighborhood were flooded pretty bad. I had to get to work and I did not know they would be that bad and had to drive through a good amount of water. My check engine light came on and my EPC light too. And I noticed that my car is super shaky while in idle. I'd like to know if you have any idea what's wrong and my cheapest fix because I'm not rich by any means. Thank you

My car has 130000 miles.
My car has an automatic transmission.

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Hello, The check engine light may have come on for many different reasons, however most likely as a result of driving down a flooded street, this may have caused various sensors to get wet triggering the rough idle. The crankshaft position sensor or camshaft position sensors are two critical sensors that may cause the engine to idle rough if they are wet causing them to relay intermittent signals to the ECU. The EPC light is your car’s Electronic Power Control light which refers to the throttle by wire or the throttle control system, however this can also indicate additional problems as well related to other things. The cruise control, traction control and throttle body are also other things that may need to be checked when this light comes on. You will likely need to have the computer scanned to determine what specific codes may be coming up to correct these problems. I would suggest having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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