bubbgs1

I have a 99 cherokee sport 4.0. Suddenly started misfiring bad. Replaced plugs. Cap, rotor, and wires are new. Showing p0132 02 code and po455 code.

BlueRidgeMark

That's interesting.

Do you have a question?

bubbgs1

Thinking it may be the o2 sensor. Gonna replace it n see

Precept

Have you changed injectors? I put what I thought were better injectors on my jeep (not realizing they were not correct for the 4.0 Liter engine). My jeep miss fired at certain sporadic intervals. I put the original injectors back in and no more miss fires.

extrashaky

Since you have a code for it, that's probably a reasonable thing to do.

Since you also have a code for a vacuum leak, it's also reasonable to look for said vacuum leak and fix it.

tjwalker

Links below to descriptions of your codes and what you should be looking for.

The P0455 is likely not related to your symptoms but should be resolved. If you replace one oxygen sensors, replace BOTH of them as the other is likely not far behind. Use only NTK oxygen sensors, OEM brand for your 99.

https://www.yourmechanic.com/article...ank-1-sensor-1

https://www.obd-codes.com/p0455

extrashaky

Very reasonable advice. Everyone's very reasonable today.

bubbgs1

Thanks guys. Picked one up yesterday gonna change it later

bubbgs1

Figured out my problem. Blown head gasket 😔