I have a 1989 chevy sububan 3/4 ton I need to know where to place the o2 sensor in the exhust.?

Question

I need to know if it goes before the catalitic converter or after I would look at the old exhaust but I don't have it.

Answer 1

Look at the emission sticker under the hood. In 1989, not all vehicles were equipped with converters or oxygen sensors. If you life in a city that requires Emission Testing, you need to have the vehicle put into original equipment specs. If you are getting the exhaust pipe from a part store, it will already be threaded for the O2 sensor. If you are planning to cut a hole into the pipe and then weld a nut to hold the O2 sensor (IT IS A "PIPE" THREAD)
you may not find the nut to fit it. You can not just thread it into the pipe.
All this said and done, in that year the O2 was directly in front of the converter.

Answer 2

This is an older truck so there was only one O2 sensor used. It was placed in the Y-pipe or the down pipe ahead of the cat. convertor. The only vehicles that use before and after O2s are 1995-6 and newer. They are called OBD2 as the emissions were a lot more strick. If you are tricking up your motor, just get it anywhere you can for the signal as it doesn't affect this type of system except to irritate you with the SES light. I would suggest one thing, install it in a place where there is a lot of heat as these diagnose bad if they have a drop in temp. while running. Hence the reason they are installed close to or in the manifolds. Good luck.

Answer 3

It's in the exhaust system - right after two pipes from exhaust manifolds merge, before the converter.

Answer 4

Usually before. Most cars have them on the exhaust manifold, but I'm not 100% sure on your suburban.

Answer 5

Upstream of the catalytic converter and usually below the headers. Exact positioning is not important. Many engine modifiers move it to where it is convenient.

Answer 6

most older vehicle o2 is on the manifold