Wideband 02 took a dump I think! Ideas?

[No Quarter]

FAST system wideband 02 sensor looks like it took a ****. I have a static A/F via the fast log of 14.98 - its a flat line. Never moves. Any ideas of what it could be beside a dead o2 sensor? I suppose she could be burnt up. I was running waaaay too much timing. Here's a pic of the log.

 

[norbs]

Disconnect power to the ecm for 30 seconds, then reconnect it. SOmetimes it "locks" at a certain a/f for some un explained reason. If thats not it, unplug, and replug in the sensor, sometimes the pind push in a bit losing connection.

 

[No Quarter]

Originally posted by norbs
Disconnect power to the ecm for 30 seconds, then reconnect it. SOmetimes it "locks" at a certain a/f for some un explained reason. If thats not it, unplug, and replug in the sensor, sometimes the pind push in a bit losing connection.

Are you saying shut the car off and log another run? Or actually disco the neg battery terminal? Is there anything that can be used to clean them?

 

[tazgn]

I recently posted about mine doing the EXACT same thing. It happens at random times and with no fix except turning the car off and letting it set for a while. I think it's a freak bug with the FAST system. My VGOS (or whatever they are called) voltages change, and the car runs good. So I would suggest doing like me, and when it happens, that the FAST system's way of saying F*** off I'm done for the day, come back tomorrow.

Derrick

 

[No Quarter]

Originally posted by tazgn
I recently posted about mine doing the EXACT same thing. It happens at random times and with no fix except turning the car off and letting it set for a while. I think it's a freak bug with the FAST system. My VGOS (or whatever they are called) voltages change, and the car runs good. So I would suggest doing like me, and when it happens, that the FAST system's way of saying F*** off I'm done for the day, come back tomorrow.

Derrick

The original log was two days ago and still I have the same problem in later logs. I'll try the above ideas, if that does'nt work I'm forced to order a new one

 

[Craig Smith]

It does not appear that the sensor is lighting off in this log. The best sensor to log when troubleshooting O2 problems would be UEGOS. It should stabilize around 0.45 volt when everything is happy. Make sure the lambda symbol still appears on your screen when you start C-Com - if this doesn't appear, the sensor will not light off. Also, make sure you still have 12 volts going to the sensor with the key on. This will be a blue wire on the sensor if it's one of the newer style sensors, or the orange wire on the older style sensor. "New" sensors have L2H2 stamped into the sensor bodies, and the older ones have L1H1 stamped into them.

A failed sensor is a possibility here, but there are a few things you can check in the mean time.

Derrick, you might want to check a few of these things yourself if this problem creeps up on you again. Pay attention to the UEGO, UEGOS, and UEGOR voltages during a problem period and let us know what you see. That info will tell a lot about what is going on. If we were looking for ways to tell you that the ECU is done for the day we could do a LOT better than that!

 

[norbs]

Unplug the ecu from +12v lead from the battery. PLug it back in about a minute. Start the car, see if you get the a/f fuel ratio changing. I also had some erratic readings the other day, turned out the ignition wires were to close the the o2 sensor, causing severe fluctuations.