foul plugs

[WRXracer]

I know I must sound stupid with all these questions.. but yesterday when my alterater hit my hood all this platic crap melted all over and it was arking and making my car run like crap.. there was black smoke everywhere car was way way rich.. now I fixed it and the car is running way better but seems to be a little bit hesitate.. could i have fouled my plugs running it soooo rich..

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