I have a p0303 fault code. Miss fire #3. I
have changed the plugs the coils the maf
sensor and the pcv valve but still
missfiring. I also have oil threads of #3
P0303 TOYOTA - Cylinder 3 Misfire Detected...Possible causes; Faulty spark plug 3, Clogged or faulty fuel injector 3, Faulty ignition coil 3, Fuel injector 3 harness is open or shorted, Fuel injector 3 circuit poor electrical connection, Ignition coil 3 harness is open or shorted, Insufficient cylinder 3 compression, Incorrect fuel pressure, Intake air leak...The P0303 code means that the cylinder 3 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 3. If the problem persist more tests needs to be done to diagnose problem.
There are no leaks on intake and I've already changed plugs and coil over.
There is more to check.
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