Code: P1133 I need any help/info on code P1133 for a 2005 Chevrolet Silverado 1500 2WD

DTC P1133 HO2S Insufficient Switching Sensor 1
What other codes , need to diagnose those codes before P1133 !
Important: If any DTCs are set (except P1133 or P1134), go to those DTCs before proceeding with this diagnostic table. If the vehicle is misfiring is there a DTC P0300 Engine Misfire Detected code ?

http://www.obd-codes.com

Here's a link to your code. P1133 Chevrolet HO2S Insufficient Switching Bank 1 Sensor 1 Hi Frank,sounds like your oxygen sensor is bad,you didn't state your engine size,I will send a couple of firing orders so you will know where bank 1 is which is cylinder one which means the sensor is screwed into the exhaust manifold cause it's bank one,bank two would be at cat. converter.Here's the 4.8 engine firing order. Specifications Firing Order AutoZone com Here's the 5.3 engine. Specifications Firing Order AutoZone com Here's the 4.3 engine firing order. Specifications Firing Order AutoZone com

Code 1133 is when the O2 sensor in front of the catalytic converter on bank one does not switch back and forth between rich and lean.
The problem could be a faulty sensor or something with the fuel mixture. The sensor would need to be tested.

The code means the ECM doesn't like the exhaust mixture coming thru the cat.
It could mean one of the O2 sensors has failed, but could also be caused by a list of other problems with the fuel-air mixture.
If the ECM can't adjust the fuel trim to keep in the range, the cat could be damaged and fail inspection, so the ECM turns the light on and goes into safe mode until the problem is fixed.

This code is for insufficient switching of the oxygen sensor. Make sure you don't have any other codes, misfires, vacuum leaks and/or exhaust leaks as these will affect O2 readings. Here is some more info I found on the web. http://m.engine-light-help.com/?url=http%3A%2F%2Fwww.engine-light-help.com%2Fgm-trouble-codes.html#3331

P1133 CHEVROLET - HO2S Insufficient Switching Bank 1 Sensor 1http://engine-codes.com/p1133_chevrolet.htmlForum CodePossible causes- Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 shorted to Engine Control Module (ECM) ground
- Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1
- Vacuum leak
- Faulty Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 connector and wires

Your O2 sensor is starting to go bad .recomend replacement before it gets worse

Code P0134 is the #1 oxygen sensor on bank 1, up near exhaust manifold.
Code P1133 is insufficient switching of bank 1 02 sensor. Need to replace it.

p1133 - o2 sensor, Insufficiant Switching, Bank 1 Sensor 1.
p0131 - o2 sensor circuit, low voltage, bank 1 sensor 1
p0171 - Lean condition, Bank 1
p0300 - Random Misfire

I would be looking at the front passenger side oxygen sensor for issues. It may be bad, it may not be plugged in, bad wiring at harness.

The random misfire may be symptomatic of the o2 sensor problem.