I am working on it the guy i bought the car off of replaced the rear o2 sensor with a wideband for some reason. I thought you were supposed to install it in the down pipe and leave the stock o2. So i am ordering a new o2 sensor and i also have a mutiple cylinder misfire code caused by the cams i guess, I am setting up a dyno tune at a local shop hoping i can get rid of the cel lights.

 

yeah, your supposed to keep the stock 02 sensor and just add the wideband on. But an easy way to get the check engine light to go away when you get rid of the converter is to make a spark plug de-fowler or how ever you spell it, it helps.

As for the misfire code theres a thread in the faq's about it.
here it is from the thread...
It seems there is an issue with the code in the Evo ECU that causes a check engine light due to an 0300 misfire code. This seems to randomly occur on stock and modified Evos. Apparently, there will be a reflash available from Mitsubishi to correct this issue. A few others have replaced and re-gapped their plugs and found this to help the issue. At this time, there does not appear to be a clear fix.

anyways, hope this helps a bit. Good luck tuning

 

on gas pump 21 with a safe tune. you running 93 so is all good for 21psi. fourth and fifth gear will be higher with a tune. and the HKS is Bov will not recurculate so take it off your car is bad for you.

 

take the bov off and run 21