O2 Sensor Question
 

I am replacing all four of my O2 sensors. I ordered some off of ebay. The pre-cat ones were the correct oval plug, but the post cat ones came with the square plug. Mine are all oval plugs. I have looked at Mike Focke's O2 page and he has:

986-606-127-01 2000-2002 in front of the starter catalytic-converter

986-606-128-01 2000-2002 after the starter catalytic-converter

The one I bought that fit the pre-cat is the above part number. I can't find the 986-606-128-01 part for around the same price. My question is can I use the 986-606-127-01 part for post cat? Is there a true difference in the parts?

I appreciate any help.

Thanks,
Chris

The sensors are the same except the post cat has a longer wire.

What is stenciled on the old and new post-cat sensors? What brand are they?

And consider the equivalent Bosch brand sensors (I did) as Bosch makes em and Porsche only labels them with a part number, puts a box around them and prices them.

Mike,
I looked for anything written on the old sensors and could not find anything. I am pretty sure they were replaced in 12, based on the service records I was able to obtain. I am guessing they replaced them with no name versions. I am thinking I am just going to get the same kind I did for the pre-cat (they should fit). I reviewed your page pretty in-depth. Thanks for all of the part numbers. That helped.

Chris

Bosch sensors have the Bosch part numbers on the sensor. Porsche sensors have both the Bosch number and the Porsche part number. I'm cheap but not daring. I used the Bosch.

The length of the pigtail is the difference. I always assumed that the additional length of the post cat version was needed perhaps to avoid contact that would burn through the insulation.

That list has been up for maybe 10 years and I've referred people to it many times over the years and no one has ever told me of any needed corrections. I'd appreciate it if anyone finds anything outdated or wrong about it if they would tell me and I'll correct it.