Cat delete on early 1997 986
 

I have a set of Che cat bypass pipes and after getting under the car and ready to install them, I come to realize I have an early 1997 Boxster that has a single cat on each side, the 2 O2 sensors are in the same pipe as the cat (before and after the cat). The bypass pipe only has a single bung for a O2 sensor.

Question is what to do - scrap the bypass pipes all together? Weld a second O2 bung in the pipe? Tuck the second O2 sensor out of the way, leave it plugged in, and hope to not get any fault codes?

Thx!

Use the search function as this has been discussed at length. If memory serves me you could use them as long as you get your DME flashed with a ROW program. But don't quote me on this- search!;)

Get an ROW re-flash and you will only need one oxygen sensor on each side.
That's what I did...you also can remove your secondary air system with the flash...saves weight.

Thanks for the thoughts - I have searched but forums but not much has been discussed about the early '97's - as I understand they have a DME that is not able to be re-flashed.

You mention removing a second air system, I presume you are referring to secondary cats - that is the issue, there is only a single cat on the early '97's.

I am ready to forget the cat delete at this point as I do not want cel's.

Thanks-

One thing you can do more easily than those of us with 2000+ cars is to install the ebay headers. We can't since we have the first set of cats integrated into the stock "headers" and those are the ones monitored by the system. (well we can but then we have to deal with the CEL or else get a ROW flash) Maybe you can exchange your pipes for a set of those headers, I believe they make them as well. That should give a similar boost to performance as installing the pipes.

Steve

Sorry for the confusion....I should have said "I removed the secondary air pump and the associated vacuum hoses." My car is a 1998 and my DME was 5.2.2 version BUT I can not answer your question about a 1997 re-flash.......I have heard they present issues with a re-flash. Jake Raby would know the answer to that question

steve has a good point - most put the bypass pipes on because changing the headers is a pain given that they have cats on them. you have the opportunity to put headers on easy. the engine benefits from having the obstruction (cats) as far downstream as possible.

otherwise, if you can't reflash, try just disconnecting the second set of sensors and hang them under the car - see if you get a cel. some have found that this works. if not, then a second set of bungs is required. you can get expensive sensor foolers (like these:

FVD Brombacher Online Shop - FVD111LAMVER - Oxygen Sensor Extension - EXHAUST → Tuning → Catalytics

or make your own out of a set of spark plug spacers.

Great information! Thank you very much - looks like headers are the best and easiest option for me. Last question, I see there are long tube runner and short tube runner versions, any idea which is the appropriate option?

Thanks!

A place called Big Daddy's garage has them as well, $14.95 for the spacer and around $50 for one that has a mini cat built in.

O2 Simulator, mini catalytic Converter cel fix

Also an early 97 here...I simply zip-tied the second set up out of the way...no CEL, no issues...