My 2001 Tahoe has the Service Engine light lit, and my scanner reports code P1133.

Heated Oxygen Sensor (HO2S) insufficient switching bank 1 sensor 1 (Rear Bank)

I purchased the replacement sensor at my local parts store, however can someone please shed some light as to where exactly switching bank 1 sensor 1 is?

is it before the cat?

Thanks!

 

There are four O2 sensors, sensor 1 & 2 on banks 1 & 2.
Bank one is the driver's side.
Bank two is on the passenger's side.
Sensor one is before the converter, and sensortwo is behind it.

 

If the new sensor does not correct the DTC follow these steps:

Check for the following conditions: [align=left] • An improperly installed air cleaner outlet duct [/align] [align=left] • The air cleaner outlet duct for a collapsed duct, restrictions, or a missing or plugged air filter [/align] [align=left] • Throttle body and intake manifold vacuum leaks [/align] [align=left] • A damaged or blocked throttle body inlet [/align] [align=left] • Exhaust system for corrosion, leaks, or loose or missing hardware.
[/align] [align=left] • The HO2S is installed securely and the pigtail harness is not contacting the exhaust manifold or wires [/align] [align=left] • The vacuum hoses for splits, kinks, and proper connections [/align] [align=left] • Excessive water, alcohol, or other contaminants in the fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis [/align] [align=left] • PCM sensor grounds are clean, tight, and properly positioned [/align]

 

Thanks guys! very much appreciated.

I will follow up here with how I make out.

 

I replaced the sensor sunday afternoon, and cleared the P1133 code with my Actron OBD-II handheld.

So far (knock on wood) the service engine light has not come back on.

Generally, how long does it take for the computer to reset, and would show an error again if it were still a problem?

Thanks!

 

Service Engine Light just came back on, however I am now getting error code P0446 :
Diagnostic Trouble Code (DTC) P0446
DTC Definition: EVAP Emission Control System Vent Circuit Malf


Any ideas?

 

Install the new evap cannister vent valve, P/N10382105

 

Is that a GM part number?

I'm trying to find it at advanceautoparts.com, so I can pick it up locally...

 

where exactly is this cannister vent valve on my tahoe?

 

GM Part#
The canister is located underneath the Tahoe just beneath the driver side door on the inside of the frame rails. The valve is located at the front of the unit. It is shaped kind of like a large pack of cigarettes.