justanotherperson

the car is an 02plate WRX with only 2 mods, a Green cotton air filter changed about a month a go and a decat middle section with an after market lambda sensor,both fitted at the same time about 2 weeks ago.

The car run and feels fine although i didnt boot it,but the light did come on after about 2 miles of warming up,ie not reving above 2000rpm.

The light is solid and doesent go off, i have re-started the car 6 times just to check this.

I have the car booked in at Main dealer tomorrow to have the fault code read,

My question is:If subaru find it is the middle section lambda sensor (after market NOT original cos it stripped) will an original Subaru sensor cure the CEL light or will it keep coming on because the cat is now gone?

thanks
J.A.P

brunny42

decat middle section, there are not any cats in the middle section, there is a cat in the pre turbo up pipe and 2 in the down pipe section, the funny looking box in the centre pipe just after the flange is a resinator box, and not a cat, have a look in your hand book it clearly shows you where the cats are located, i think from memory it is section 2-9 around the CEL light information sorry chapter 8 page 3

justanotherperson

There is a cat on the up -pipe one one the down pipe and one in the center section as well as the resinator box behind the said cat,making three in all,i know for i have just had it taken out and it is sitting outside in my yard,

Thanks for trying to help with the cel,i'll just have to see what comes up tomorrow

hades

Brunny - not true, There is one cat in the downpipe, (and one in the up-pipe) and a cat in the "front centre" section as it has been christened in bugeyes, and then a resonator in the centre section. Therefore the two part centre section has a cat and a resonator

To answer the original post - it's impossible to tell without knowing what fault code has come up.

There are a few codes relating to the rear lambda sensor - cat inefficiency low (which shouldn't happen with an up and downpipe cat fitted), and one or two relating to sensor response time as well. It is possible that the aftermarket Lamda sensor contributed to one of these problems.

It could also be one of a number of other codes. I find my 02WRX (with a few more mods than yours) tends to throw a misfire code on one cylinder if I haven't used it for too long (one outing in a couple of weeks is not enough) - that is not related to the lamda sesnor at all.

brunny42

Brunny - not true, There is one cat in the downpipe, (and one in the up-pipe) and a cat in the "front centre" section as it has been christened in bugeyes, and then a resonator in the centre section. Therefore the two part centre section has a cat and a resonator


well i have a bugeye, just checked on my office roof, thats where my old cats are kept, the down pipe is in 2 sections, but is the length of a classic down pipe, so suppose you could say the 3rd cat is either part of the down pipe or part of the centre section, personally as the 2 cats are in the down pipe, i class them as in the down pipe and not the centre section, plus when you purchase a centre and rear exhaust from most places, you only get from and including the resonator back over, i know from experience that certain well know companies which i wont name still claim they arte selling decats but are not. IMHO