True or False???
 

Question. I was told by a 18 year Porsche Master Tech. that if I remove the 2nd set of cats on my 2000 Porsche Boxster S that the check engine light will come on.
Can this really be ture?

Just disconnect the front O2 sensors and find out.
 

Really think you are going to gain that much HP with just an exhaust tweak?

Not sure about the Boxster, but this can be true with other cars. I think some of it depends on whether or not there are O2 sensors after the 2nd cat.

True, it is mainly because of the disconnected 2nd 02 sensor.

On the Boxster, the secondary O2 sensors are after the pre-cats i the headers, not the secondary cats. The car cannot tell if the secondary cats have been removed.

Patrick

Your 18 years of experience (or is it 18 years old) Porsche Master Mechanic is wrong. The O2 sensors are on the header cats (1st set) like bmwm750 stated. No way for a CEL to come on.

This is absolutely false. I took the secondary cats off over a year ago and have driven thousands of miles on and off the track. No CEL. This really isn't something to do to gain HP as you will never notice the difference but it will alter the tonal quality of the exhaust which can be just as rewarding as a few HP.

Porsche Master Tech... don't always trust those words...

hahaha... how tru, how tru....

The tree huggers will find you and key your car.

BEWARE! :barf:

Do you have emissions testing in PA? If so, wouldn't you fail without the second cats? :confused:

MOST of the counties in PA have emmissions. With the exception of a few, however, they're visual only. So a lot of cars like these can get away with "Yep, there are still cats on it!" as long as the mechanic doesn't know it's supposed to have two :)

I don't get it. Aren't there 4 sets of O2 sensors on each sets of cats? Right. The 2 on the 1st set which are located on the headers and the 2nd set which are on the down-pipe just before the exhaust. So that makes a total of 4! As long as you keep the 1st set with the headers that use a bung hole for the O2 sensors the cell should not come on. The second set of cats also uses O2 sensors, and if you were to buy an after market set of by-pass pipes they would still need the bung holes for the sensors. So maybe the Porsche master tech thought the removal meant the sensors too, and not just the cats. :confused:

On a 2000 S, this is not accurate. There are (on each side) two O2 sensors. One before the primary cat on the header and one directly after it, also on the header. There are no other O2 sensors.