Code P1133 [Archive] - Forum


View Full Version : Code P1133

06-18-2009, 06:05 PM
The Definition is:

BBH02S-11 insufficient switching
BBECM has detected the switch ratio of rich to lean lean to rich was below a determined number
Probable cause
BB1- Failed H02s11- heater circuit
BB2- H02s-11 signal shorted the ECM ground
BB3- Improper oxgen supply to sensor- Check sensor connector and wires

Does anyone know what sensor is causing this code?


Mike Jung
06-18-2009, 06:24 PM

Code Make Description

P1133 Pontiac HO2S/O2S Insufficient Switching Sensor 1 Or Bank 1 Sensor 1

Sounds like the 02 sensor in the downpipe before the Cat.

Have a peek at this:

06-18-2009, 06:44 PM
Thanks Alot!!

06-18-2009, 07:04 PM
Also, you can check for a melted O2 sensor electrical harness.