Hi everyone, just bought my first Jeep ever the other day. It's a 97 Sport with the 4.0 and a manual transmission. It's in really good shape overall, the only rust is on the front fenders which someone covered up with some cheesy diamond plate fender protectors. This is going to be a vehicle for my daughter for the next couple years, so I am planning on not sinking too much money into it until she's done with high school. Once she finishes up then Dad gets a toy and I'll replace the fenders... Assuming she doesn't wreck it. She loves Jeeps, so this should be a fun father/daughter project.
So, now the bad. A previous owner removed the catalytic converter and left the downstream O2 sensor hanging, which eventually broke in half. I'm actually glad they didn't just unplug it, because at least the connector was still in good shape and not corroded when I unplugged what was left of the sensor. Of course with this kind of hack job the CEL is on, and I have P0141, P0138, and P0320 codes.
I'm reasonably certain the P0141 and P0138 are both due to the missing cat and sensor, but is there any possibility that those could be the cause of the P0320? I've read that the CPS can cause that code, and since it's an older vehicle maybe I should just replace it anyway while I'm at it. If so I'll go with a genuine Mopar part, but I'm a little confused what part number I need. Do all the 4.0 TJ's need the same sensor? Different parts houses online have given me different part numbers.
I have a complete new exhaust from the manifold back on order, along with new NGK O2 sensors, so hopefully soon I'll have this thing back to running like it should.
So, now the bad. A previous owner removed the catalytic converter and left the downstream O2 sensor hanging, which eventually broke in half. I'm actually glad they didn't just unplug it, because at least the connector was still in good shape and not corroded when I unplugged what was left of the sensor. Of course with this kind of hack job the CEL is on, and I have P0141, P0138, and P0320 codes.
I'm reasonably certain the P0141 and P0138 are both due to the missing cat and sensor, but is there any possibility that those could be the cause of the P0320? I've read that the CPS can cause that code, and since it's an older vehicle maybe I should just replace it anyway while I'm at it. If so I'll go with a genuine Mopar part, but I'm a little confused what part number I need. Do all the 4.0 TJ's need the same sensor? Different parts houses online have given me different part numbers.
I have a complete new exhaust from the manifold back on order, along with new NGK O2 sensors, so hopefully soon I'll have this thing back to running like it should.
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