O2 sensor issue

Hi!

I have some problems with my car (rover 216) and i suspect faulty O2 sensor. Because i dont have oscilloscope i measured with analog V-m: Heres is the clip:



So please let me know if this O2 sensor works flawless or not ?

Regards,

Jurif

How expensive is it to replace it? Sometimes it's easiest to check a part by trying another one, but that can get expensive.

Without a data sheet for the part you're trying to trouble shoot, it might be a little difficult. There are a couple different automotive types (5 wire versus 3 wire for example) and they all utilize heating elements. You would need to test one with some knowledge of what you're looking for and it wouldn't be a single measurement that determines whether the device is working properly or not. You'd need to check the heating element for one and then the sensor over a range of conditions. I would imagine automotive shops typically utilize engine controller fault codes to identify failed O2 sensors. In fact, they probably do that for most engine faults.

You dont need a Scope to check an O2 sensor. Yours apears to be working as its switching HI/LO, if it was reading only high or only low then there is a problem. Here is a little tester ive built & used for years diagnosing either faulty O2 sensors & fueling problems. Ive used long leads so it can be temporaily set on the dash for road testing. It should show ritch when acellerating & lean when decellerating, when cruising it should be constantly switching HI/LO.

Heres a bit of basics on how they work & testing a typical Bosch HEGO.