changed O2 sensor and engine light won't go out....help!

**leitchfield** · 12-18-2010, 11:15 AM

ok getting pissy with this thing. 2001 tahoe 5.3 engine...4x4, auto...etc...
its had check engine light on for a few months now and i finally got around to checking it and it was the bank one sensor one O2 sensor code...and that was the only code in there...so i changed it out, had the battery unhooked for oh 30 minutes or so while i was changing it hooked it all back up, and i have drove it for about 20-30 miles and the light is still on...???

i changed one of these same O2 sensors out in my 99 silverado 5.3 and when i hooked all back up and drove it for a little bit the the light went out on its own...and all is well....

so tell me do i have to get this silly computer flashed to clear the code out??? on an 01 vehicle? or whats the deal????

**Justin_Inc** · 12-18-2010, 11:32 AM

unhook the battery over night, that'll clear the memcal in the ecm, hook it up, if the light comes back on in 150 miles that means you didnt fix the issue.

**redvett01** · 12-18-2010, 11:38 AM

Codes cannot be cleared on OBD2 without a scanner. Have the code read and cleared.

**mudbuddy** · 12-18-2010, 12:46 PM

Originally Posted by redvett01

Codes cannot be cleared on OBD2 without a scanner. Have the code read and cleared.

^X2 funny how guys are still telling people to unhook the battery.

**leitchfield** · 12-19-2010, 08:14 PM

light went out on its own after a half days driving.....nice. on day two now and light still out.

**6.0 Bowtie HD** · 12-19-2010, 08:37 PM

It has to run a number of engine cycles not reading the code and it will correct itself. From what I gather in other places.

**redvett01** · 12-19-2010, 08:52 PM

After any repair on OBD2 vehicles your supposed to clear the codes but if the repair is successful the PCM will turn off the SES light. The history codes will remain until cleared with a scanner.

**Justin_Inc** · 12-19-2010, 11:14 PM

Originally Posted by mudbuddy

^X2 funny how guys are still telling people to unhook the battery.

unhooking the battery on OBDII vehicles does work, but its not a 20min procedure like with OBD vehicles. 24+ hours are needed. try it one time. Do it long enough and sometimes you even have to reset the VATS system for it to start again.