I recently put a new 350 engine with vortec heads in my 92 camaro. On top of the engien I have a FAST 4150 throttle boby with 36 lb injectors. It is controlled by a dynamic efi computer. This is basically a stock computer that can be programmed. I also have a wide band O2 sensor connected to the computer. The wideband sensor indicates the engine is running rich also indicated by soot on the driveway after idling. The stock o2 sensor indicates a lean condition. This sensor came out of the old engine and has about 30,000 miles and 10 years on it. Should I replace it? Thanks.

 

I had a defective O2 sensor in a TBI pickup; read accurately at low throttle settings, went lean as the RPM went up.

Replacement of the sensor cured the false lean indication and trouble code.

As inexpensive as an OEM O2 sensor is, replacement makes sense.