Today mid way through my commute to work my cruising afr's went all the way to lean......Typically my crusing afr's bounce between 14.3 and 15.1. Under greater WOT percentages my AFR's richen up nicely to exactly where they should be and the sensor reflects this.

Why would cruising all of a sudden go straight lean? Is the sensor going bad? Im at a loss. Sensor has been in car for about 1 year now exactly all under E85 conditions.

 

Just a reading spike or the gauge stuck there?

 

stuck there until I dip into the throttle more aggresively.

 

Mine did the same thing 2 days ago and now it's STUCK at 14.8. The sensor is brand new. Wtf.

 

Does it keep happening i.e. everytime you cruise around or is it still stuck now? When you blip does it go right back to lean? Does it do the start up routine correctly?

 

Try to disconnect and reconnect the sensor, use electrical contact cleaner to clean it also.

 

May be a bad sensor. Same thing happened to me, I changed the sensor and it worked perfect again.

 

Sensor, mine lasted about a year before replacing and went back to normal afterwards.

 

Just drove to lunch and at idle or crusing (sub 25% throttle open) it is all the way lean. Before today it would be between 14.3 and 15.1.

When I blip the throttle and get into any kind of boost the sensor reads normally. The guage richens up as it should. It is just idle and cruise that pegs all the way lean now.

 

Seriously I have lost my mind. Bought a new sensor and come to find out the second bung on my downpipe had the plug back out. That is why it was reading lean. I didnt really notice the exhaust leak because currently I used the OEM gasket on my MAP O2 elim by accident and I am having a bit of dump at idle. I need a beer and a break. ha ha

 

Check and see if sensor is bad - http://www.youtube.com/watch?v=1mb4VmDd0ao

 

It's stuck at 14.8 all the time. Even at WOT. I'm gonna work on it today and
Figure out what's going. I'll chime back in and let you know what happens

 

i had this happen to me, but mine was an easy fix. the connector wasnt all the way in. if your saying its plugged all the way in check your pins and make sure there not bent. also check your o2 wires and make sure none melted on your exhaust. that would give you a false reading

 

I'll check that today. Thanks man. I'll let you know. Thanks man.

 

Yeah, I had something similar happen to me. My UEGO's O2 sensor had backed out of the threaded bung located on the testpipe. My gauge needle had frozen at a single reading.

Dumb me I went ahead and ordered a new sensor. When I got under the car to install the new sensor II discovered that the old one was still perfect. It had just backed out. Or, I'd forgot to reinstall it when I had done some exhaust work.