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Q: Rough idle

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My car was running fine, came home from work and parked it. The next day it was idling rough. Wiggled the map sensor connector and it would idle fine. Did that for 2 days then replaced the connector. Still giving the same issue so I just replaced the map sensor itself and now it seems worse. Idles rough enough now that it kills the car. What do I do next?
My car has an automatic transmission.

A: There are several possibilities for a car t...

There are several possibilities for a car to have rough idle. You may have a bad mass air flow sensor. I would suggest having the system checked with a scanner to see if all the engine sensors are reading the correct data. Have tests done to see if it is the mass air sensor or a defective map sensor, or potentially another issue that is going on. A technician from YourMechanic can diagnose the rough idling fault and let you know how to best proceed with a repair.

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