alright, i'm getting realy tired of my suburban.

back in may service engine soon light coame on, code was P0137 (o2 sensor low volts Bank 1 sensor 2)

changed o2 sensor still got the code.

changed both cats and the other 3 o2 sensors.

didn't get anymore codes.

2 months ago light comes back on, code is p0137 again. didn't feel like doing anything cause i was pissed about.

yesterday, swapped the rear o2 sensors bank 1 to bank 2 and vise versa.

reset the computer. (the codes before i reste the computer were P0137, p1406, p0137)

20 minutes later, poped the codes again.

this time they were, p0137, and p0157-o2 sensor low volts bank 2 sensor 2

details on this thing. i've got 145,000 on the suburban and it runs good, no mods aside from a K&N filter. everything else is stock.

i'm taking it to the dealer tommorow because i've got to drive to virginia in 2 weeks and i'll be towing my jeep. can't afford to have a failure in route.


any ideas.

by the way last may, when i replaced evrything i went ahead and put new plugs and wires. everything is serviced and maintained very regularly. engine is extremely clean (very anal wash it often).

map/baro sensor. sound like it could be just worn out or its got a vaccum leak.

I have a 97 silverado, I went through the same thing. Cant tell you which thing finally fixed it but this is what I did other than all the o-2 sensor changing like you did.

1 new cap/rotar

2 new fuel filter

3 new exhaust ( cats where pluged, and the flowmasters had seen better days)

Honestly I think what really did it was simply the fuel filter sense the check engine light kept coming on every now and then when I would climb hills or towing.

sorry not vary helpfull but thats what I did, and have not had the check engine light on in awhile.

Hi again,
I did some checking with my Gm buddy today. he thinks you may have bad wire or rubbed through wire in the harness going to the o2 sensors. he said the codes are inconsistant voltages from the o2's.
the most likely place to find a rub through would be where the firewall meets the floor next to the bell housing....happy hunting.

chevy said it was the 2 back o2 sensors. these were after market Bosch sensors, and i had heard that often times these don't meet the parameters for the computer diagnostics. they lasted a couple months before they dropped below specs.

ended up buying two o2 sensors from chevy for $130 each. :shaking:

ended up buying two o2 sensors from chevy for $130 each.

ouch!