I have an ef with a minime swap in it, zc block, y8 head, z6 intake.

I’ve installed an arm Wideband cause it’s such a weird build I wanted to monitor stuff.

I used the bung from the stock 02 which is vertical on top of the exhaust between firewall and oil pan.

When I start the car the gauge goes crazy bouncing all over the place from 13 all the way to 18. It typically fluctuates between 14-17 and sometimes pegs lean

my idle surges. Idk if that would affect the afr that much or what’s the issue is it really that lean? As in dangerous to drive? Or could it be a sensor issue or wiring issue?

I pulled the sensor and smothered it with a carb cleaner rag and it pegged it all the way rich….

just not sure what to do or where to go from here. I have so many hrs into trying to get this running right I’m so overwhelmed

 

what type of Wideband? That location and "angle" isn't ideal for a wideband.

 

You can damage your sensor cleaning it. They are not meant to be cleaned. If it a old unit, my autometer wideband pamphlet mentioned if the reading is acting up, most likely the sensor needs to be replaced or if yours is too far away then that might cause a issue. The sensor placement should fairly close to the head, I think within 18" or so..

 

^^^ agreed. Mine is mounted right on the DP, between the radiator fan and block.