Scotty, I’ve been driving around an 04 Jeep Liberty 3.7l v6 for about 5 years now. Just recently got to 170,000 miles. A few months ago the check engine light came on for a bad o2 sensor bank 1sensor 1 so I replaced both front ones together. Drove it after getting it back from the mechanic and the light came back on. This time for bank 2 sensor 2 (p0159) coupled with a 02096 fuel trim system 1 lean. I also noticed some gas in my oil and figured the engine is trying to compensate to pump gas into the system. Would the o2 sensor cause this to happen.? Ant if not should I look into leaky injectors, possibly weak fuel pump? Just replaced plugs and coil packs 500 miles ago, I’m at a loss!
Generally bad sensors never do that odds are with that mileage the engines wearing out and it's running at an incorrect air fuel ratio and then it trips those codes because it's confused and sees weird data. It may be time to get rid of that jeep
If the compression on the engine is still good would that show there isn’t as much wear? When I did the plugs all cylinders were running at 180