VR6-er

Hi Guys,

This weekend I fitted my CAT bypass and whatever I replaced (not sure if its a CAT) didn't have an O2 sensor in it. My mate Dave suggested my 964 looked as if it was running rich and trawls of the internet suggest that this is a symptom of not having the O2 sensor.

My Car is a 1990 model. Would a UK car been sold without this?

The CAT bypass has an O2 sensor hole, I'd like one.

Andy Roe

They were all sold with an O2 sensor. My guess is the previous owner replaced the cat with a bypass pipe without the sensor hole - they're cheaper. If you look into the unit you removed you'll be able to see the honeycomb inside if its a CAT.

Only buy the Bosch part for the 02 sensor.

Andy

Andy Roe

..

g60pops

put a photo up of what you removed to confirm whether it is a cat.
I got my bosch lambda probe from Euro car parts as they were the cheapest with their 25% off offer.

VR6-er

g60pops, I'll do that when I get home.

VR6-er

Andy,

I remember it does have something in there, how much is the bosch sensor? Cant find it on EuroCarParts.

Andy Roe

Type911 have it at £76+vat.
Design911 at £98.50

freedman

Does your car have a loop out plug then? (fits where the 02 sesor goes to in teh engine bay)

If not you need one if not running the sensor

VR6-er

Thanks Andy.

Hi Freedman,

I don't know know what it looks like, or where it goes, can you point me at pics?

time666

Hi Vr6-er, what cat bypass did you get? Reason i ask, is i got a fairly cheap and cheerful one from ebay and not fitted it yet. Im just hoping the match it good and angles of flange fittings match the original.

freedman

http://www.porsche.com/all/media/pdf...64_KATALOG.pdf

Loop out plug part number

911 612 422 00

Its item 32 on page 111 of the above PET, and Porsche just call it an 'adaptor'

It sits in the engine bay, left hand side as you look at it in a clip on the chassis rail. Fits in teh connection the Cat would have gone into

VR6-er

I got the same one and it fits a treat. Its a doddle to fit as well. I gave the nuts a blast of wd40 and they came apart easily. The flange on the heat exchanger is rotten, but has some life in it for now.

VR6-er

Thanks for that, the Loop out plug is there. Would I be right in thinking that the automatic adjustment of the Fuel air mix is lost without an o2?

http://forums.pelicanparts.com/porsc...-question.html

freedman

Not sure about that

Mine got a bypass with a loop out and I cant say it runs any differently than it did when it had an 02 sensor in it