OK, 1999 Cherokee Classic with 85k miles. All stock. Real nice shape but keeps posting a check engine with a P0137 on my OBD2 scanner. Replaced downstream O2 sensor. Checked vacuum lines. Checked O2 fuse. Checked both O2 sensor connections for corrosion. Reseated MAP sensor connector and cleaned out throttle body with carb cleaner and Seafoam. Jeep is all tuned up and runs fine. 18 mpg in mixed driving. Exhaust system is good. Very annoying. Anyone with ideas on this?
Thanks, FM
Thanks, FM