I'll try to make this brief:
2012 JKU with newly replaced driver cyl head.
Check engine and popping sound happened after replacement and dealer recommended coils. Had them replaced.
Plugs also new. Added new gaskets to upper intake mani.
Still now getting P0300 and P0302, P0304 but it's intermittent, sometimes runs perfectly fine, other days it'll crop up and very randomly it'll stumble, lurch, and have intake popping noise.
Sometimes takes 3 seconds to start, but usually fires right up.
No loud head ticking, but can see driver upstream O2 sensor read high when misfiring. Reads fine when not.
When it really had a bad morning it threw a bunch of codes, but usually just the P0300 or P0302 or P0304.
I've got coil, plugs, lower PUG intake manifold (dealer stripped plastic threads in original so I'm trying to rule out loose intake)
I even have injector o-rings as I'm considering removing them and having them cleaned.
Also will look for ground wire or harness connections.
Didn't want to take it to the dealer as they love to charge for random things before getting to the real problem.
(them: "you need plugs" me: "They are brand new" or "$200 fuel treatment" they merely dump in the tank...)
I hear it's possible that the replacement head could be bad as well?
2012 JKU with newly replaced driver cyl head.
Check engine and popping sound happened after replacement and dealer recommended coils. Had them replaced.
Plugs also new. Added new gaskets to upper intake mani.
Still now getting P0300 and P0302, P0304 but it's intermittent, sometimes runs perfectly fine, other days it'll crop up and very randomly it'll stumble, lurch, and have intake popping noise.
Sometimes takes 3 seconds to start, but usually fires right up.
No loud head ticking, but can see driver upstream O2 sensor read high when misfiring. Reads fine when not.
When it really had a bad morning it threw a bunch of codes, but usually just the P0300 or P0302 or P0304.
I've got coil, plugs, lower PUG intake manifold (dealer stripped plastic threads in original so I'm trying to rule out loose intake)
I even have injector o-rings as I'm considering removing them and having them cleaned.
Also will look for ground wire or harness connections.
Didn't want to take it to the dealer as they love to charge for random things before getting to the real problem.
(them: "you need plugs" me: "They are brand new" or "$200 fuel treatment" they merely dump in the tank...)
I hear it's possible that the replacement head could be bad as well?
