2001 Ram 1500 Oxygen sensor

Mar 19, 2007 2 Replies

Check engine light came on. (84,500 miles on the 2001 V6) I had Autozone test it. Says O2 sensor is failing. But he mumbled about it being the "second bank" sensor. I never clearly understood what he was trying to explain, I think the readout on the testor said "PO128."



Any idea what that means? Are both sensors the same? How hard is it to crawl under there and replace?



Thanks!



Nope - maybe P0158 (that's bank 2, sensor 2).

Well, actually you have four sensors - two pre-cat and two post-cat. You need to know the exact code to pinpoint which sensor it's complaining about.

You don't need to go back to Autozone, though - you can read your codes by cycling the ignition key. Start with the ignition in the 'OFF' position. Turn it ON, then OFF, then ON, then OFF, then ON. Leave it in the ON position on the third time (you need to do this all within about 2 seconds). Watch the odometer. It will display all it's stored diagnostic codes, finishing with 'Pdone'. Write the codes down, and post them back here. You can also look them up at the following web site (among hundreds of others):

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Thanks Tom. Great tip on the key cycle ON/OFF. I had no idea! The code reads P0138.

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