Is the car going into limp mode? Mine does this when ever I wash my engine, the reason is due to a fault, or an arc in the ignition. When it happens it is like the engine is running on 3 cylinders, no power. I have to shut it off and re-start it, it is fine and then it will do it again until it dries out. I don't wash my engine anymore, but if you have faulty plug wires that are arcing or causing attenuation that faults the computer and the things goes into limp mode. Just an idea, can't really diagnose without more info. Good luck!
Brian

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Brian W. Heitman

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