I was out driving today and my o2 started reading no higher than .55V. It also wasn't registering any change between half throttle and full (boosted) throttle. I fear I may be running dangerously lean. The only thing I've done recently is bypassed my stock boost controller in order to run safer (less boost). What's going on?

 

How old is the sensor?

 

when your running WOT it doesn't use the signal off the O2 sensor, chances are your O2 sensor is on it's way out

 

anybody else?

 

dude it's as clear as day .. chances are your O2 sensor is shot..
no one else is saying anything cause there's nothing more to say

just get a new stock O2 sensor if you don't wanna spend alot of greens

 

the problem I have is that it registers 0 change between half and WOT. What regulates fuel under WOT?

 

me

 

hahahha no, seriously, it use static WOT fuel map...

 

Lol, seriously, the O2 sensor inputs should be constantly moving- even at stoich the meter needle bounces back & forth between .4 and .5v, so, an A/F gauge should be showing the same thing, albeit in a different format...

If the readings are stuck, either the sensor is bad, the gauge is bad, or you have a teeny tiny wiring problem...

 

narrowband o2 sensor should not be used to check afrs during boost.

 

I know, I just figured I'd see it go from 14.5 A/F and at least move a little when I get on it hard.