i have had a MRT header on my car for a while, but now i am getting a CE light, i know this has been post many times but i do not know what to do.

any help will be aprecciated!!

you don't have many options...
1. Ignore it. I have a ce light, and I've had the code pulled, and it's not anything serious, and it's not hindering performance...
2. take the bulb out (see 1)
3. You might trying to swap the stock muffler on to the mrt system and see if it get's rid of it. I've heard that this worked on the a legacy.
4. Sell the system and go back to stock

Sorry to not sound positive, but noone yet has solved the ce light problems, I'm not thinking they will.
AO <- w/ MRT & glowing CEL too

yeah! i know it is not a big problem, but since the CE light is on my car is having problems with mpg. it spending too much gas

hey ,
no ! you do not want to pull the light out or ignore the CE light ...........
1st when the CE light comes on for any reason the car runs rich....
2cnd if your car has any other problems how will you know ??


to solve it .... i would say cut where the O2 sensor is on header then weld a after market CAT ... im not sure that would work on a subaru but i would be trying things to get that light to work properly or just take the header off and sell it :) ...
oh and you cant by pass the O2 either because its a closed loop and your computer needs that to mix fuel and air ....... just thought i let you know :) laters

how can i weld i cat to my header??

the header replaced the cat under the car right ?? if it did where the long pipe is under the car cut and paste :) i dont own a header yet and im not positive it will work on a subaru ......... so if you got room take it to a mufflar shop and ask them ........
gl

The exhaust comes w/ a high flow cat included. The o2 sensors are 1 before the cat, and one after the cat. The reason for the code is catlitic converter effiency (not any other reason), and my car isn't running rich because of it. My milage is close to the same, 350 miles per tank, which is less than stock, but the whole idea of headers is to increase the amount of air & fuel flowing into the engine, therefore using more fuel.

With that said... try the stock back box, see if it helps.
AO

I don't have an aftermarket header, but while I was driving on Sunday night, I got a CE light when I let go the throttle. My A/F meter went nuts after the light came on. It couldn't decide to run rich or lean while cruising.

I drove 120 miles after that, then disconnected the battery for about 3 hours, and reconnected. No CE light ever since then.

i have tried reseting the ECU but it does not works.

I just want to know why does the CE comes on? if it is because is getting direct gases, i thought about rapping around the sensor a little metal net, the same material that comes inside the catalyst (if you see a catalyst form the inside you can see lots of nets one after the other)

can this be done?

Santo, not to be harsh, but as usual you haven't read what people have posted here (namely m750) and you haven't bothered to search to find your information. The caust of the MRT header CE light is well documented, as is a possible cure. But you won't read this either, and will ask the same questions down in this post, so I'll stop here.

The metal matrix inside a cat is made up of precious metals, including platinum. It reacts with exhaust gases to render them (mostly) harmless. Even if you were able to find a "metal net" made of such material, and could wrap it around, it wouldn't do anything...but clean the air a little bit.

A little searching will do you good.

Julian

I have the Borla headers, stock cat, Stromung mid-pipe and muffler. I got the CE light when it got cooler outside. I gather that the stock headers (which are insulated) heats up the cat much quicker than the Borla and other non-insulated headers. The ECU monitors the O2 sensors and expects a certain value from them a certain period of time after startup to verify that the cat (and other components of the exhaust) are working properly.

The first time the CE light came on, I did an ECU reset and it was gone for a while.

The second time I left it alone and it went out on its own for a while but came back on and has stayed on since then. Maybe the ECU gives the systems a second chance to show they are working properly before setting the code in the ECU permanently (until cleared manually)?

Anyway, it's annoying and you won't know when something else goes bad, but I try to ignore it for now until I figure out a better solution.

On a side note, I read about a local shop building a header with hi-slowcat attached to it for the RS that they may GUARANTEE WILL NOT THROW CE LIGHT.... I may just end up swapping out the Borla header and stock cat for this piece if it is not too $$$$$.

Luigi