Ya - I was looking at that - I'm a 97 - don't need an O2 bung - the O2 is on the pipe behind the Cat.

I'll do some measurements when it's up on the lift this weekend and see if it would clear.

 

None of us need rear o2's. It doesn't even throw a code.

 

0707
Your Maxima engine is OBD-2 compliant. All Diagnostic Trouble Codes are four digits, with the first is always 0 or 1. Therefore your "77" is actually "0707" which points to the rear Oxygen Sensor.

Your Maxima has three Oxygen Sensors. Two are front sensors, mounted in
the Y-pipe between the exhaust manifolds and the Catalytic Converter. One
is a rear sensor, mounted in the exhaust pipe downstream of the Cat.

When both front Oxygen Sensors are operating normally the rear sensor serves only to keep tabs on the Catalytic Converter. That's the reason your engine is running well. The Engine Control Module (the computer) is not using the signal from the rear sensor to control engine management functions.

 

You can put an O2 simulator for the rear one. But without a cat or simulator you should get a code.

 

If the front two are working properly the rear isn't referenced. I've had mine disconnected for 1000 codefree miles.

 

Whoa - Hijack!

 

I don't know if that's because of your 95 ECU, but at least on 5th geners you get a code even by leaving them connected but just zip tied hanging.

 

On my 4th gen, as soon as the rear O2 is disconnected, then SES turns on.

 

Mod.....please......split....post!

 

My rear o2 has been zip tied to the body for almost 3 months and has not thrown a code

 

my rear O2 is still in without a cat and is giving me a code. will the code go away if I take the O2 out and zip tie it somewhere?

Nate