First a disclaimer... I'm OK around cars but not a mechanic by a long shot...
I have a 2002 Hyundai Elantra and initially had a check engine light come on and when I had it scanned it showed a P0303 misfire code, but the car still ran really well.
I checked the odometer and it just hit 106,000 and I realized it's been a while since I've had the plugs and wires replaced so I started with that hoping that would solve the problem but it didn't.
A friend suggested that I replace the coil pack, so I replaced it but that didn't fix it.
A relative checked and found that I had a bad air intake gasket and he said that could cause the problem too, so we replaced it and while we were at it also replaced the valve cover gasket and exhaust manifold gasket just to get those out of the way.
I continued driving the car and it progressively has gotten worse, and started throwing a P0302 code and a P0300 code.
I read online about the o2 sensors, so I decided to replace both the upstream and downstream sensors... still have the misfire.
Continuing to troubleshoot the issue I decided to replace the camshaft and crankshaft position sensors. Still a problem.
I replaced the MAP sensor, still a problem.
While looking at the scan tool I noticed my throttle was moving even though I wasn't moving it, so I replaced my throttle position sensor... scanned good, but still didn't fix my misfire issue.
Normally I would have taken the car in but I figured for the cost of labor I could have new parts... but I figured I would have solved the problem by now. Any help or suggestions is appreciated!
I have a 2002 Hyundai Elantra and initially had a check engine light come on and when I had it scanned it showed a P0303 misfire code, but the car still ran really well.
I checked the odometer and it just hit 106,000 and I realized it's been a while since I've had the plugs and wires replaced so I started with that hoping that would solve the problem but it didn't.
A friend suggested that I replace the coil pack, so I replaced it but that didn't fix it.
A relative checked and found that I had a bad air intake gasket and he said that could cause the problem too, so we replaced it and while we were at it also replaced the valve cover gasket and exhaust manifold gasket just to get those out of the way.
I continued driving the car and it progressively has gotten worse, and started throwing a P0302 code and a P0300 code.
I read online about the o2 sensors, so I decided to replace both the upstream and downstream sensors... still have the misfire.
Continuing to troubleshoot the issue I decided to replace the camshaft and crankshaft position sensors. Still a problem.
I replaced the MAP sensor, still a problem.
While looking at the scan tool I noticed my throttle was moving even though I wasn't moving it, so I replaced my throttle position sensor... scanned good, but still didn't fix my misfire issue.
Normally I would have taken the car in but I figured for the cost of labor I could have new parts... but I figured I would have solved the problem by now. Any help or suggestions is appreciated!