I have a 1992 Chevy S-10 blazer with the 4.3L V-6 and TBI fuel injection. It dies when it's idling and the computer code says the oxygen sensor is bad. I don't know why it's only got 198,000 miles on it.

Does anyone know where this sensor id located? I looked over the exhaust manifolds and I can't see it.

Edwin

 

On some vehicles I've seen it was located around the Catolytic converter.

 

My 97 4.3 had 4 oxy sensors in it before the howell harness eliminated two of them. There are two types of these. Upstream between the engine and cat, and downstream after the cat. My 97 had two upstream and two downstream. The harness eliminated 2 of them because there is no cat now. I'm not sure how many yours has. It should be close to the manifold if there's only one tho.

 

The older TBI units only had one O2, I believe. It'll probably be in the 'Y' pipe that connects to the manifolds. My old Blazer had it on the driver side of the Y pipe, about 10 inches after the exhaust manifold.

greg

 

Thanks guys! I'll have to crawl under it tomorrow and scope it out. The parts store wasn't any help and they had 3 different sensors so I'll have to crawl under, take it off, down to the store, crawl under again to put the new one on.

Nothing is ever simple.

Edwin

 

Check the drivers side exhaust manifold tucked up by the floor pan or as mentioned behind the intersection of the y pipe. It should be the cheapest one they offer. GM didnt use anything but one wire O2 sensors on the first 10-20 years of fuel injection.
You may have a bigger problem than an O2 sensor though. The computer shouldnt go into closed loop running until it gets readings back from the O2 sensor after it warms up. This usually takes 2-5 minutes of the car running. If it stalls after initial start up you will need to look another place. The IAC valve would be a good place to start. They get carboned up over time and cant control the idle correctly. Stalling or a hanging idle speed are a good sign of this. Usually you can pull it out of the throttle body and clean them with carb cleaner and a rag.

 

Your O2 sensor is on the passenger side right at the side of the transmission on the exhaust pipe. Which fueler does it have? Exactly which code is present?