MSP exhaust

[Nima_What]

about a week ago my cataltic converter got messed up for some reason, so i took it the muffler shop and the guy said that there is 2 cats so instead of putting in a new cat he just put straight pipes in that portion of the exhaust. and today while i was driving home my check engine light came on. do you think that since the emisions are a little higher my light came on or do you think something else is wrong? because my engine seems fine.

 

[cmahlig]

its the o2 sensor. since you have no cats your o2 sensor is throwing up a flag. only way to cure it is with a mil eliminator or non fouler. i got my mil eliminator from apexr1.com its like 20 bucks. you just splice it into the wires and i havent had a problem since. i thought california had pretty tough emission laws so you might wanna go ahead and put a highflow cat on there.

 

[lisevolution]

That's exactly your problem... I have a single high flow cat and use the non-fouler trick. Costs like $1 from the autoparts store and however much your exhaust guy charges you to install it on the pipe. The biggest positive over the MIL eliminator is that you don't have to cut the wires on the o2 to splice anything in. Other than that they both do the same thing

 

[GingerBreadMan]

you can also use a sparkplug non fouler to get rid of the cel if you dont wanna mess w/ wires. it puts the o2 sensor further away from the exhaust gas flow and tricks it into believing there are cats. worked for me and many of the guys on the wrx forum.

 

[Nima_What]

cool thats what i thught , ill probably go with the non fouler.

Thanks

 

[GingerBreadMan]

just remember to reset your ecu... unhooke battery and pump your brakes a few times. the cel will be gone. if the cell doesn't come on after a few hundred miles, you should be all set. if it does, don't be discouraged, mine came on after 500 miles, and i reset the ecu again and it didn't come back after that.

 

[Kansei]

Did he remove both cats or just replace one and put a straight pipe in place of the other? If you have the single high flow cat, your emissions levels once the engine is warmed up will be nearly the same. The initial cat is a "pre-cat" or "warm up cat".

But yeah, if he replaced both with a straight pipe then that would definitely explain your CEL. The spark plug nonfouler trick is easy and works, but it's merely a poor bandaid over a much bigger problem.. you're missing vital emissions control equipment and yes, causing more pollution and freakin out the ECU.

 

[Nima_What]

only one of my cats was bad, so he put straight pipe instead, i still have one of the stock cats.

 

[Kansei]

only one of my cats was bad, so he put straight pipe instead, i still have one of the stock cats.

He probably took out the cat before the oxygen sensor, which yeah would cause that problem definitely. The sensor has no idea that there is still a cat, just right past it.

 

[Nima_What]

should i go wilth the mil eliminator or the non-fouler?

 

[lisevolution]

they both do the same thing, just via different methods... I personally didn't like the idea of splicing my 02 sensor wires which is why I went with non-fouler method... My thought was that if I ever wanted to return to stock I wouldn't have to worry about that being an issue.

 

[Kansei]

Plus, nonfoulers are like 3 dollars for the two you'll need.

 

[orng1]

I guess I've been lucky, I'm only running one non fouler and haven't had any issues.

 

[h8rsnv]

im gettin a cat back exhaust. so should i just get 1 high flow cat? any clue where i can get them from and the cost?

 

[Swerny]

im gettin a cat back exhaust. so should i just get 1 high flow cat? any clue where i can get them from and the cost?

cat back exhaust starts after the cat section. Therefore you won't need additonal cats.

 

[h8rsnv]

yh but a high flow cat will provide better flow. so i guess i could just replace the 2nd cat with a high flow cat from catco or magnaflow right?

 

[Swerny]

yh but a high flow cat will provide better flow. so i guess i could just replace the 2nd cat with a high flow cat from catco or magnaflow right?

you're not understanding me.

The cats aren't in the cat back....they are before it, in the midpipe.

If you get just a cat back, you won't change the stock cat setup.

If you also want to upgrade the midpipe, there are several vendors here who can hook you up.

I would go with one good high flow cat in place of the 2 stockers, with an O2 bung after the high flow cat.

That's what I have, and I still pass emissions testing

 

[h8rsnv]

well im i bought a custom one that comes with a custom midpipe and hks muffler. unless ur sayin i have to buy a midpipe that with 1 hi flow cat that replaces both cats. any suggestions where i could get all of this. sorry for bein a newb with exhausts.