91' legacy 2.2l, only has 1 02 sensor..

anyways, both my cats plugged up, blew one out into the muffler, to make a long story short the exhaust was toast..

 

so i cut out both cats, fabricated a new y-pipe without a cat, and straight piped to the factory muffler..

problem solved.. car runs super now. will actually pull hard to redline with ease and has a bit of a subaru rumble to the exhaust tone now.. overall i'm happy..

 

but in the process i neglected to put an 02 sensor back into the exhaust system.. its just simply unplugged and sittin on my bench..

 

i've put 100 miles on it so far, no adverse effects and no check engine light..

 

so realistically is there any reason i should put it back in? cause i really don't want to take my 1-piece exhaust off again lol..

If you don't mind 20 mpg running in open loop then by all means leave it off. Pretty much defeats the purpose of fuel injection to have no O2.

 

GD

I am pretty sure it's illegal to cut out the converter and not put it back on.

I am pretty sure it's illegal to cut out the converter and not put it back on.

 

considering most shops will cut them out here i doubt it.. but we don't have emissions or inspections here anyways..

 

and yes i know it makes my car pollute more, etc.. if i had the $400 to get a header and cat from a 2nd gen legacy i would.. but when the budget is non existent i gotta do what i can...

I am pretty sure it's illegal to cut out the converter and not put it back on.

 

Only if you drive it on public roads. He never specified that it's not an off-road only application. In which case DOT regulations do not apply. But yes - it is against FEDERAL law to modify factory emissions equipment. Not that this law is enforceable in any way - but it does exist.

 

GD

considering most shops will cut them out here i doubt it.. but we don't have emissions or inspections here anyways..

 

and yes i know it makes my car pollute more, etc.. if i had the $400 to get a header and cat from a 2nd gen legacy i would.. but when the budget is non existent i gotta do what i can...

 

I'll sell you a Wagner aftermarket cat for $100. PM me.

eventually i'm going to replace it all with the 2nd gen style header and cat, but until the $4 shows up. it'll have to do.. i am going to weld in an 02 bung tho and put the sensor back in..

Put the sensor back. It will run better still with the sensor in place and working.