Engine light on after oil change.
 

Like so many others, for the past couple years my '07 Jk has been burning a lot of oil between changes. After much debate and researching on the Internet, I decided to try 5w30 synthetic instead of my usual 5w20 synthetic, as a lot of people say this fixes the burning issue. Changed my oil yesterday, put about 100 miles on it over the weekend and all of a sudden the check engine light lit up. Seems like an unlikely coincidence that it's happened right after the oil change.

Any suggestions? Should I just cut my losses and go back to 5w20? Do you think that will make the light go off?

The oil change is most likely unrelated. The first thing you need to do is scan it and see what code/s pop up.


Turn your key from off to on position 3 times and report what code pops up on the instrument panel. On third on leave it in on position. No start is required, just on position.

Thanks, buddy. It came back with a P0430 code. Looks like something with the catalytic converter? Maybe exhaust? As far as I can tell there are no exhaust leaks. Should I assume my converter is F'ed?

I would start with o2 sensors before spending money on a CAT. How many miles on it? Generic o2 sensors are usaully a lot cheaper, the only difference being you splice in the new o2 to the old o2's pigtail.

I would also double check for exhaust leaks especially from your exhaust manifolds. I have change both of mine because of cracks as long as 2 inches.

It's got 120,000 kms, so that's about 75,000 miles. I hear some emissions stuff is covered up to 8 years? Would that include the cat and o2?

A quick search shows that the CATS are covered 8 years/130,000 kms in Canada. O2 sensors will most likely not be covered. I would be bringing it in to the dealer ASAP.

Thanks, dude. Much appreciated!!!

Good luck.

P0430 - Catalyst Efficiency (bank 2)

I would change the O2 sensors first before taking it to the dealer. By any chance do you hear a rattling from the mini cats? I had one on my WJ break apart and rattle.