I just got done installing Buschur's TBE on Saturday night/Sunday morning.
And tonight my engine light popped on. We had a lot of trouble getting the O2 sensor out of the mid-pipe.

Not sure what it could be, my guess is something to do with the change in air/fuel ratio. It does sound a little whistley, maybe an exhaust leak from an unclamped bolt?

Any thoughts would be great, thanks!

 

You can guess its an exhaust leak or you can get it scanned and find out its probably the P0420 code.

 

What's the code mean?

 

Catalyst Efficiency Below Threshold
https://www.evolutionm.net/forums/sh...ad.php?t=69304

 

P0420 is Catalytic Efficiency Below threshold Bank 1,it is not that your rear o2 sensor is bad, It means that your TBE w(test pipe or hfc) is not working as well as the stock cat converter and the ecu is telling you this. You need an anit fouler or a rear 02 simulator. Search the forums and you will find all you need. Search for "02 fix", "02 simulator" "P0420" Youll find answers.

 

By saying "...not working as well as stock...", you mean it's actually working BETTER as far as performance goes, AKA flowing better?

 

yes.. But the ecu thinks something is wrong.