Okay the header arrived and the cat should be there soon... So to save me money, we are going to do the header swap ourselves but everything after will be left to the muffler shop... will driving about 2 miles (maybe less) while throwing a CEL be unsafe for the car... this is going to be done in a VEEERY small town in South East Idaho so noise pollution is not a concern, just my car's engine.

 

the CEL is nothing more than the 02 sensors tripping your car's ECU off to possible problems.

since you'll be reinstalling the 02 sensors as soon as your new header and catback exhaust, the CEL should theoretically turn itself off.

but hey, that's just theory. lol.

 

u'll be fine...my friend has been driving his 02 SI around with test pipe and throwing CEL for months now and car stillruns like a champ.

 

yea same here ^ althgouh i think i'm in limp mode, 2 miles isnt going to hurt anything. You might still throw the CEL anyway becasue of the new cat, you may need an o2 simulator, or you may be one of the lucky few that gets away without needing one.

 

Youll be in limp mode.

civicracerex... your buddies si is not running like a champ... its in limp mode

Flip... youre in limp mode.

 

do you actually lose horsepower in limp mode? Like honeslty if you took it to a dyno and ran it with a CEL vs.without one, would you get different numbers?

 

yes, you lose power... about 5-8hp. And your gas mileage goes to hell.

 

damn, i need to get a simulator asap [&:]

 

ask around, i thought i read something here that you shouldn't run just a header due to the fact that cold ambient air can flow back up the header and that it isn't good for the engine to shock it from ingine temperatures straight to ambient air temperatures. check it out though because i am not sure.