Air Fuel Ratio Changes

[forumboarder154]

Okay I have searched for threads and found nothing like this. Somedays my car will run a little richer than normal like around 12.8 at cruise or sometimes around 15.6 or sometimes normal. Anybody no why this is? I have a aftermarket Bosch front o2 sensor. Also I bought the wideband used off a race car. I have no clue maybe someone has experienced this problem or maybe I am paranoid and Mitsubishi has crappy ecus. It just seems like a car should run the same all the time.

-Kyle

[Black_Bullet]

What are you tuning with, what air sensor do you run ( i.e. 2g mas, stock 1g mas, gm maf, 3g mas)?

[forumboarder154]

stock 2g mas hasn't been fooled with all honeycombs are in.

[forumboarder154]

Maybe a bad wideband o2 sensor?

[JayRolla]

Any boost leaks?