Problem started with a jerk , loss of power and resumption normal. Then problem moving away , jerking , loss of power. Got worse jerking , no increase of rpm for more gas . car starts easily . slight surging and low idol speed . can increase this with the throttle. when idling , taken off plug leeds one at a time . runs on 3 cylinders hear that all 4 go when leed replaced.Opened air filter to see if there was O2 starvation. Slight but not excesive backfiring
My car has 150000 miles.
My car has a manual transmission.
The jerking may be related to what is called a mass air flow sensor which is a unit that regulates air flow into the intake as it is mixed with fuel prior to being injected into the motor. When this is not working correctly, this can cause the jerking problem you are describing. This can also contribute to the backfiring problem if the engine is running lean. I would recommend having an expert from YourMechanic come to your home to diagnose and repair.
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