Need help on which O2 Senors to purchase please
 

My car: 2003 Boxster S.

I want to replace both of these O2 Senors circled in red.

http://i57.tinypic.com/214a0b8.jpg

They are the oval plug connector type. Are they both the same unit?

My car has 4 O2 Senors per side and looking at Pelican for O2 Senors with oval plug connectors I get a bit confused as they show 1 Bosch (Before Starter Catalyst, Left or Right).

Then they also show the Bosch (After Starter Catalyst, Left or Right)

So which ones do I want to order to replace both the O2 Senors circled in red??

Porsche Boxster (1997-2004) - Exhaust Pipes, Manifolds & EGR - Page 1

Thanks!

I think I have it figured out, please correct me if I'm wrong.

I need parts 26 an 27 in this diagram?

http://i59.tinypic.com/2cmmely.jpg

So that would be part numbers 986-606-227-00 and 986-606-228-00?

http://i58.tinypic.com/2ufgb5d.jpg

So I need to order these?

Pelican Parts - Product Information: 986-606-227-00-M14

Pelican Parts - Product Information: 986-606-228-00-M14

They are the same except the cables are two different lengths, hence two part numbers. Search for "mike focke boxster" he has a website with all the part numbers and he explains it better than I can. Yours may be different though since you have 2003, I think they may have changed.

You need 1 before and 1 after catalyst if you want to change them both.

Yes I believe you have the right part numbers.

Thanks steved0x!

when I replaced mine, I used the bosch universal ones and they are working fine for less than 1/4 of the price for the oem replacements. just a little bit of clipping wires and connecting to the existing plugs. I am sure I will hear it.... yes I know I am a sinner.

try getting the old ones out first !

That's not a problem. I have the proper tool to remove them and have removed one just to look at it.

May cats are bad and so are my O2 Senors. I'm putting headers with 200 cell cats on the car. I'm going to put new O2 Senors on them. So the removal of the old O2 Senors isn't an issue.

You are forgiven. I have heard people say to replace all 4. Any truth to this?

But why replace 4 when only one is failing?

You can make an argument for the two matching fronts (they usually are the first to fail) just because they get the same exposure and the car is on the lift and the muffler system is cool and you may save money (PS, any muffler shop can do a single O2 sensor for 20 minutes of labor, no special Porsche tools/knowledge needed. The local muffler shop did mine.).

The car now has 117k miles on it. I'm sure they are the original O2 Sensors. I didn't take the time to check each one individually with the Durametric tool, but the tool reported in the ready status that my O2 Sensors failed. I do all my maintenance, no need for me to take it to a muffler shop. I have the proper tool you need to remove and install them properly.

http://i61.tinypic.com/ifdcn8.jpg

http://www.ebay.com/itm/271561301844?_trksid=p2057872.m2749.l2649&ssPageNa me=STRK%3AMEBIDX%3AIT

http://i59.tinypic.com/oa0qpi.png

Thanks for the ebay link. I got to replace mine too.

You're welcome.

My Fuel tank ventilation was do to my gas cap having several cracks in the seal. Got if off eBay too and issue fixed.

http://i61.tinypic.com/2nbskzl.jpg

1999 2005 Porsche 996 C2 C4 Turbo GT3 Fuel Gas Cap with Clip New | eBay

That's good.. obviously the weather in Kasas City isn't as destrimental as the UK. i had to replace the O2 sensors on the range rover last saturday. a couple of hours of heat, pb blaster, turn a bit with a breaker bar on the O2 socket, wiggle back and forth rinse and repeat.. finally got one out.. i left the other one till this weekend.

i thought the O2 sensors were going out on the boxster and was really not looking forward to that joy... 4 heat and corrosion 'welded' in live data seems to show its the MAF. i'm more pleased on that funnily enough !


That's one of the many things i miss about my time in the US (SoCal) cars dont corrode up to the eyeballs and you guys have garages that can actually fit a car in !

There are specific codes that detail what is wrong with the O2 sensors. Short, aged, etc. I'd be very surprised that a Durametric couldn't be very specific as a generic code reader will pick up the specific fault and the specific O2 sensor.

For example the P0159 gives you a post-cat bank-2 aged description.

Usually, it is the pre-cats that fail first at around 60-70k miles.

Good luck, they can be difficult to get off.

These are the only fault codes Durametric is giving me. I'm installing them on new headers with 200 cell cats, so removal is not an issue

http://i57.tinypic.com/2d8gb2q.png

The one O2 Sensor I took out came out without any problems. I did check my MAF sensor with the Durametric, it's functioning fine.

Here is where what I think caused my cat problems. My AOS was going out, not doing the heavy smoke deal or anything like that, but when I put in the new intake system there was oil in the Distribution T and the line from the AOS. Why this AOS didn't just give up and blow like most I don't know, but it went on long enough that my car threw a CEL for the cats. So I'm pretty sure they are mucked up and bad.

The P0446 happen because I tried a home made repair to the gas cap seal. Not sure what I did wrong because when I would go to put fuel in the car, it would take several cranks to get the engine started again. Replaced the "repaired" gas cap with a new one, code is gone and the car starts right up now after being fueled.

Yes that would do it! however, burning oil can mess up the cats too. I'm hoping for you the O2 sensors solve it.

Fingers crossed!!

Anyone tried using NTK 25601 O2 sensors instead of Bosch ?