Oxygern sensors - how many? (KV6)

[Blink]

The product description box on this Rimmers page says there are only two oxygen sensors on the KV6 exhaust. The original cat on my Mk1 KV6 has three! What's going on?

[T-Cut]

I notice Rimmer's detailed listing shows the number required as 'a/r' which I guess means 'as required'. Early cars have two and later ones have three, but I don't know when it happened. I think it was when the OBD regs appeared.

TC

[Blink]

Ok, thanks TC.

[Blink]

TC - is it ok to re-use the old washers when refitting these sensors?

[ryszard]

Hi,I have a complete spare exhaust off a mk1 V6 2.5 X reg car and it has 3.One on each downpipe and one past the cat.Regards Ry...

[T-Cut]

Originally Posted by Blink

TC - is it ok to re-use the old washers when refitting these sensors?

I'd have expected a new lambda sensor to come with a new washer. They're compression washers, so a new one's better than an old one, but I guess an old one will still compress.


If it's of any help, an old sensor can be easily tested if you have access to a propane torch and a volt meter. A volt meter across the leads should indicate around 1 volt when the sensor tip is very hot. If no voltage the sensor has failed.


TC

[Blink]

My car came off the line in May 2001 so the changeover from 2 to 3 sensors was before then.

[Blink]

Originally Posted by T-Cut

I'd have expected a new lambda sensor to come with a new washer. They're compression washers, so a new one's better than an old one, but I guess an old one will still compress.

New sensors do come with washers (e.g. link) but the washers themselves don't appear to be available separately. The old ones on mine don't look very re-usable to me and it's a bad place to find you've got a leak (or three leaks in this case).

Originally Posted by T-Cut

If it's of any help, an old sensor can be easily tested if you have access to a propane torch and a volt meter. A volt meter across the leads should indicate around 1 volt when the sensor tip is very hot. If no voltage the sensor has failed.


TC

Thanks for the tip - I'll remember that if any of mine appear to be duff.

[Blink]

Rave says discard the washers and fit new ones.




p673

[T-Cut]

Originally Posted by Blink

New sensors do come with washers (e.g. link) but the washers themselves don't appear to be available separately.

If I had to resolve this, I'd measure the OD/ID/thickness of the required washer and search eBay for something suitable in the same material. eBay has millions of washers in every shape/size imaginable. https://www.ebay.co.uk/sch/i.html?_f...asher&_sacat=0

Do you have the dimensions?

TC