Random O2 sensor question
 

If you disconnect the O2 sensor when engine is at idle should you see any change if it is functioning as it should
THis is on another car I am working on , not an MB, but similar to the Kjet with lamda system.
And just what are the classic symptoms of a bad O2 sensor?

number 1 problem--- gas mileage dips signifigantly

number 2 problem--- engine can run a bit rougher at lower speeds


also you don't need the specific sensor.... you can get a generic one for less than half the price ... you just have to splice in wires.... no big deal

thanks Lee, i was wondering about the generics, at ( in this case) a 3rd of the cost , I was skeptical
So as long as they are compatible, splicing in will work??
and disconnect at idle - you would or would not hear /see an idle disfunction?

This car has an idle issue and I have eliminated all other factors, so I am leaning to this sensor as a possible issue, my thought is that it is not functioning at all , it has over 75K on it
Getting it out may be the other issue - :)

If the sensor fails- the car should run rich. That's the default.

I would buy a universal replacement, but find the cheapest 2-3- or 4 wire sensor and cut and splice. I think in the 90's only bosch made them. For my old benz- a 1990 302 mustang sensor, cut, solder, splice and it works perfectly. It was about $35 versus a universal @ $55.
Amazon has great prices if you want to just replace it- about a 1/3 less than most of the online automotive places.

M

AGREED.

PB blaster works wonders if yours is stuck. My universal also had anti seize already on the threads.

Have any of you tested your O2 sensors using a propane torch?

Sensor in flame => no O2 => about 1 volt
move out of flame => O2 => voltage drops to about 0
Should drop within a few seconds if good

flame test huh, sounds like a plan!