Had this for 4 yrs. now, everytime i punch it AFR
shows blank on WOT .

 

Might need to change your sensor not positive but you can try that

 

yeah sounds like the sensor might need to be replaced mine just died on me a couple days ago :/

 

any other possible reason, before i order new sensor?

 

I dont think it would be a bad sensor if you are reading numbers during normal driving. But you might want to contact your tuner, because you are most likely leaning out bad at full throttle. Not good and can result in engine failure fast man.

 

tuner first... sensor second

 

The older AEM gauges didn't read below 11:1, so when the AFRs go below that point, the gauge will read blank. I remember trying to tune my old DSM and I had to guess where the AFRs were when they went below 11.. not a great design on AEM's part. And typically when the sensor goes bad it will read stoic, or 14.7 so your sensor sounds like its fine. I would suggest getting a new gauge or going with a different wideband setup.. but on the bright side, you're not running lean at WOT.

 

call aem - search the evo X forums, I made a bunch of posts about mine going bad. AEM ended up replacing the sensor.

 

Might just change sensor its been years

 

you can reset the sensor i dont remember how but i seen it on here a few months back.

 

Usually from what I have seen when the sensor is going out, you will get weird readings (for example stay at the same a/f ratio the whole time no matter what you are doing). If you are getting reading during normal driving but not WOT, I would think it could be something else.

 

if your wideband is reading normal at idle, yor tune is going too lean for the wideband unit itself.

 

Might check tightness of sensor in the threaded bung. Mine had backed out and was giving wierd readings.

 

when it reads "---" it means your out of the sensors range, also if you've had it 4 years, you probably have the old model that does not read very low AFR's & your just off the low end of the chart, you can tell if you have the older model because there is no wiring harness, the wires are permanently attached inside the gauge itself


edit----
oops, i have a bad habit of posting a response to the op before reading whole thread......... what evo3gsx said in post #7

 

did just that..also cleaned it..prob still exist