I am thinking of replacing my stock Y pipe. I see that it eliminates some pre-cats used for cold warm up and once warm the sytem works fine. A question I have is does this activate the check engine light all the time when starting?

Thanks

 

No, not at all.

 

Your check engine light should not come on, unless you screw up installing the y-pipe. The 2 O2 sensors will need to be removed from the old pipe. Also when you tighten the y-pipe to the engine it needs to be torqued to 35-40 ft lbs to keep air from getting into the pipe. Good Luck!!

 

You mean to keep the exhaust from leaking out.

 

Thanks, appreciate the replies.

 

Thats what I mean. Either way it F****s up your sensors!!