Front oxygen sensor problem ?

[Schulmann]

I have little problem to tune my car.

I have a wideband oxygen sensor installed in the left header.
When I start my car it indicates 15.5AFR at idle.
At present my plugs still look perfect ignition and AFR wise.

However ...
Left stock oxygen sensor indicates 13AFR.
Right stock oxygen sensor indicates 16AFR.
Obviously there is something wrong.
What can cause this difference in the readings ?
After a 20-40 seconds idle my PCM tries to balance this difference and idle gets a little unstable. Finally PCM leans out AFR to 17 but still the readings are not the same on the stock oxygen sensors.

On harder acceleration both oxygen sensors tend to move to the same value around 14.7 but still there is a 0.5 AFR difference.

My clonclusion is that I am due for a new set of oxygen sensors.
Am I right ?

 

[acrdakota]

Sounds like your sensors are on the way out. Easy test is to move the right sensor to the left and vise versa. If the funky readings follow the sensors then you just nailed the problem. If you find after changing the sensor sides that the right and left bank are still reading excessively different then you have a larger issue at hand. Before I get into running through all that stuff give the sensor swap a try.

I do find it rather odd that it goes to a more normal afr in closed loop (hard acceleration) But again it could be a sensor issue.

How many miles are on the car? Whats your mod list?

 

[Joseph Dell]

which wide-band are you running? there is an "issue" that techedge is working on with some of these WBs in the vipers. could be related...

JD

 

[Schulmann]

I am using Wide Band Commander. Great tool.
It seems to work perfectly.
When I have time I will post something on this device.
Didn't swap the sensors yet but it will happen soon.
Thinking back to yesterday's test one of them must be really out because it didn't move back and forward very much at idle. Whereas the other one was moving normally.

 

[Jack B]

Try to also look at the O2 voltages, then confirm the discrepancy with adaptives that are divergent.

 

[Schulmann]

Just swapped my oxygen sensors and the output pattern followed the move: output is late, output doesn't move as much as it should, output indicates richer fuel condition.
The result is unstable idle.