4 replies to this topic

[DrDomm]

Anyone ever see this before?

 

 AFRdata.jpg   416.77KB   2 downloads

 

On the bottom is AFR.  The orange is from last year, and the blue from this year.  The problem started earlier this year at Road Atlanta.  Readings at the beginning of a session were fine, but then big fluctuations at the end.  I figured I had a bad O2 sensor, so I changed it.  This is with the new sensor.  On the dyno, their O2 sensor doesn't read like this.  So I figure it's not a problem with the car.  The gauge is AEM.  Could it be bad?  The ground is used for other things that are performing fine.

 

Just trying to figure if I buy another gauge, or try a 3rd sensor.  Any thoughts are appreciated.  Thanks.

[Glenn Davis]

Looks like a fair amount of noise getting in.  Have you been through all of the wiring?

[DrDomm]

Looks like a fair amount of noise getting in.  Have you been through all of the wiring?

 

 

I guess I could try to isolate the power and ground wires.

[Glenn Davis]

Another thing to look at is any filtering done by the data system.

[DrDomm]

Another thing to look at is any filtering done by the data system.

 

I didn't make any change, and this popped up on data midway thru a session back in March.  I'm gonna try to move the power lead or ground.