Q: Idles rough at low rpm sometimes

asked by on March 05, 2017

i replace cam shaft positioning sensor that i was what the code said was wrong . the truck will drive great but when i slow down or come to a stop the motor starts idling real rough . i throttle on it a little and it clears some time i have to hold the gas peddle a little longer to get it to clear up the truck is a 2009 ford f150 XLT 4x4 5.43 3 valve

My car has 150000 miles.
My car has an automatic transmission.

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A rough idle may be caused by many different things such as low fuel pressure, low voltage to the fuel injectors, dirty fuel injectors, a vacuum leak, a faulty Oxygen sensor or a dirty or failing idle air control valve. Any of these possibilities relate to fuel delivery issues that will disrupt the normally balanced air/fuel mixture that would otherwise allow the motor to run smoothly. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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