dpeterson3
Member
- Joined
- Feb 19, 2013
- Messages
- 8
- Vehicle Year
- 1998
- Transmission
- Manual
My 98 4.0 has been throwing a code (can't remember the number now) for bank 1 o2 sensor sluggish. Replace the sensor 2 times, and no change. The ODB-II scope shows no response from the channel (will try to pose a picture later). Yesterday, I put an actual oscilloscope on the inputs to the computer and was able to get a trace that varied between ~0.1 and 0.9 mv as it should. These together lead me to believe the input on the computer has failed. Looking at the computer, I don't see anything obvious such as a failed capacitor (no electrolytics in this one). No burned traces or signs of corrosion. My best guess is the old sensor failed connecting 12v to the input and over-volted the input. This leads me to a couple of questions. 1) Anything else I missed that I should check? No reason I see the ecm should have failed, but nothing else makes sense either 2) Send for repair or buy used? Being the 4.0 4x4 with no PATS, I can only get a 98. Local junk yard doesn't have any. 3) If I send it off, any recommendations on who would be able to work on one of this vintage?