2000 silverado

moose192 · December 20, 2006

Have a 2000 silverado 1500 with a 4.3 has a P1133 code changed the O2 sensor was bank 1 sensor 1 still runs rough smells like rotten eggs . Was told it's a ground issue are these grounds at the VCM or are these grounds to the block or frame. Thanks

jtyler12 · December 21, 2006

I sounds like a problem possibly with the Cat. converter. When they clog up they will emitt a sulfur (rotten egg) smell. I'm not sure about the 2000 Silverado, but my 4.3L sonoma had another oxygen sensor just behind the cat (toward the rear of the truck). That sensor usually doesn't have to be replaced UNLESS your Cat. converter is failed or failing.

ChevyTech007 · December 22, 2006

Here are some causes of the that code. Make sure you oil fill cap is on and the dip stick is fully seated.

An improperly installed air cleaner outlet duct

The air cleaner outlet duct that has collapsed ducting, restrictions, or a missing or plugged air filter

Throttle body and intake manifold vacuum leaks

A damaged or blocked throttle body inlet

Exhaust system for corrosion, leaks, or loose or missing hardware. Refer to Exhaust System Inspection in Engine Exhaust.

The HO2S is installed securely and the pigtail harness is not contacting the exhaust manifold or wires. Refer to Heated Oxygen Sensor (HO2S) Replacement .

HO2S contamination

The vacuum hoses for splits, kinks, and proper connections

Excessive water, alcohol, or other contaminants in the fuel -- Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

VCM sensor grounds that are clean, tight, and properly positioned