[Solomon Adjetey sowah]

My name is solomon and I recently purchased a 2012 Elantra with 135k miles on it. Recently I realized my car shakes very hard with the check engine light on so I took it to the mechanic shop and they found this code(p0304) cylinder 4 misfiring .we changed the coils and plugs but it still show the same code. So we serviced the valves and checked on the pistons too ( everything was fine there) but it was still giving us the same code. So we checked for vacuum leaks and nothing was wrong. Pls at this point am very frustrated and I need help. Pls any idea on how to fix this problem will be very appreciated thank you

 

[Scott91370]

Fuel injector?
Instead of just replacing the items, swap the injectors from cyliner 1 to cylinder 4 to see of the error moves with the change. If not then you know that's not the issue.

 

[Solomon Adjetey sowah]

Fuel injector?
Instead of just replacing the items, swap the injectors from cyliner 1 to cylinder 4 to see of the error moves with the change. If not then you know that's not the issue.

We already tried that too .we’ve tried every electrical aspect and still couldn’t find the problem

 

[vicecityegt]

If you've tried injectors, plugs, coils and still have the misfire, it's probably the ECU.

 

[BOB]

My name is solomon and I recently purchased a 2012 Elantra with 135k miles on it. Recently I realized my car shakes very hard with the check engine light on so I took it to the mechanic shop and they found this code(p0304) cylinder 4 misfiring .we changed the coils and plugs but it still show the same code. So we serviced the valves and checked on the pistons too ( everything was fine there) but it was still giving us the same code. So we checked for vacuum leaks and nothing was wrong. Pls at this point am very frustrated and I need help. Pls any idea on how to fix this problem will be very appreciated thank you

What does code p0304 bring into play, have u checked the fuel injector, camshaft lobes compression compared 2 other cylinders compression. Sounds maybe like ur changing parts and not knowing weather they are good or bad first. It could be the harness also. Well good luck with it. Yes the last guy vicecity sounds like a definite maybe.Give it a shot.

 

[animemarc3477]

I had this happen to cylinder 3 and it bogs down when I give her gas; I changed the sparkplug and coil but still had this problem so I had it towed to gurley leep "bad decision on my part" and they said it was the catalyst converter and for $3100.00 they could fix the problem. Oh hell no, so I'm going to have it towed 2 miles down the road to the shop that honors my warranty