So my Magnaflow was supposed to come in yesterday, but it did not, only my intake, of course this is after I already cut off my exhaust ready to put on as soon as it arrived!!! So I'm driving around w/ no exhaust right now, is this bad? Cat back system so its just from the cat back thats off. the Engn light is on of course, but is this doing any damage, or is it just annoying as SH*t?

 

There are varying opinions about that... Most seem to debate whether the lack or normal back pressure hurts anything...

I wouldn't go on a road trip like that.. I drove a Trans Am with only open headers to the muffler shop and she is still putting down 420hp+ to the wheels..

 

Your fine, don't worry about it. I've not ran a muffler on both my H3's for a few years now.

 

What state are you in that that's even close to legal?

 

He's here in MI, and yes it is legal because it is not that loud.... It is just an I5 with a tail pipe, no muffler.

 

Your CEL is on because of something else, all the O2 sensors are upstream from the main CAT. I would double checking your intake installation (if you installed it as alluded to?).

 

It ran like crap w/ out the muffler, I actually put the piece right behind the cat back on and that cut the noise down, and now have just coupled the whole exhaust back together until the magnaflow gets here.

I did put the intake on, the Mass airflow sensor has a square inlet that lets the air in. Anyone know which way that should be facing? Towards the airflow pointed towards the filter, or facing away from the filter, I have a feeling its backwards....