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Q: My car has a rough idle and misfires once its warmed up

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Took screen out of mad sensor and problems started from there misses and cuts out once warmed up can be driving at 60mph and it surges and cuts out while driving then sitting at stop lights it's rough and exhaust is horrible and white smoke out of one pipe and the other blows black stuff out also changed plugs and wires checked then a week later and one side was fine the other was black

My car has 241000 miles.
My car has an automatic transmission.

A: Hi, and thanks for contacting YourMechanic....

Hi, and thanks for contacting YourMechanic. First of all, the mass air flow (MAF) sensor requires its screen; the air registering through the sensor is monitored with the elements in the screen. By removing the screen, you actually destroyed the sensor. I recommend replacing the MAF sensor before testing anything else on the vehicle. If you need assistance troubleshooting this issue, or the problems continue, then seek out a certified technician, such as one from YourMechanic, to assist you with your rough idle and engine misfires.

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