bigfishmoney

I have a 2001 Hyundai Tiburon w/ 130,000 miles on engine that's throwing a CEL cylinder number 2 misfire



I have replaced #2 fuel injector, ignition coil, and checked the spark plugs



after resetting the ECU the CEL comes on again after an hour or so of relentless driving









examples:



when depressing gas pedal when going up slight inclines I can trigger the cel by giving it a lot of gas and it gives up and goes into limp mode again



or on the highway constantly at 65 MPH now it starts to sputter out the exhaust ( a spitting sound ) and the CEL comes on again putting it into limp mode an d it runs fine like that.



What could this be?









Thanks

bigfishmoney

I also replaced the timing belt a 1,000 miles ago

Stocker

Last misfire episode I had was a bad spark plug wire.

onecrazyfoo4u

Have you moved the spark plugs and plug wire to a different location to see if it follows to the next cylinder? That would be the easiest check first.

Stocker

The wires are location-specific, can't swap em around without a second set. Usually my car is reliable for long enough that when wires are suspected they are also old, and I just change them out with new.

bigfishmoney

I replaced the spark plug wires and now there is no misfire.

Stocker

I LOVE when that happens.

bigfishmoney

misfire has returned could oxygen sensor cause this? I suspect a burnt valve, car emitting black smoke as well sometimes. Picking up a low mileage cylinder head from a local junkyard

Stocker

if you are getting black smoke, it's gas and your tuning is off. A bad oxygen sensor might cause that. Get a code reader on it, and see what it says. Better yet, step up your coder reader to mid-grade, and see what the O2 sensor is saying in real time and check out your fuel trims.