Air/Fuel meter seems non responsive

[Kern Dog]

Years ago on the advice of a fellow car guy, I installed an A E M air/fuel gauge. I was having detonation issues and thought that the gauge could help me tune my way out of the problem. Over the years, I have enjoyed having this gauge because it showed in real time what was going on. You could see it move around with even a 1/4 turn of the 4 corner idle mixture screws.

Lately, the readings have stayed in the 14.4 to 14.8 range which would be great if I was running 100 % pure gasoline but I'm not. We have (Up to 10%) ethanol here so the numbers should be in the high 13s at idle and cruise.
The numbers have stayed in a narrow range lately. Before, they would run into the mid to high 11s at WOT. They would be real lean at cold idle.
I'm curious if the lazy response I'm seeing means the oxygen sensor is going bad or if the gauge itself is to blame.
Where are the gurus on this stuff ?

 

[72bluNblu]

Honestly it could be the controller or the sensor. It’s probably not the actual gauge.

I have an Innovate A/f gauge/controller/sensor on my Duster, the controller recently went bad on mine (after like 10 years). Of course they changed the connection on the sensor so I had to change that too.

There should be a way to run it through a calibration cycle, reset etc. I would start by doing that if you haven’t already, they’re supposed to be calibrated on a fairly regular interval especially on a carb set up. Anyway, the calibration cycle might fix it, or if it won’t run or respond correctly it might help narrow down the issue. There should be an error sequence that it will respond with, I know on the Innovate there was an LED that would flash an error sequence you could decode with the manual.

 

[Dave999]

check the connectors on the back of the gauge, you have 2, one brings power, one is to the sensor and includes its power.
disconnect and re connect each. they are both a bit crap. they are the style of connector usually used to connect boards inside a device. you would not normally use them poking out the back of something as an external socket... poor design, re-seat the connectors, they can shake loose. make sure that the unused wires for data logging or ECU signal connection are taped up if you don't use them

under the car for the lambda sensor it has its special connector with its calibration in, Bosch does this at the factory, it is unique to that sensor. don't take that off.... but 6 inches up the cable is a latched waterproof connector. disconnect and re-connect that.

while you are under there just check that there is no exhaust leak close by...

mine has been in for 10+ years and i have had to do this routine once....same symptoms

maybe i was just lucky...worth a try

don't think you can force a calibration on the gauge like you can on more expensive kit. i think it does it on start up every time. full sweep of the scale. pause at 14.7 for 20 seconds etc.


Dave

 

[dano]

I think to recalibrate the sensor needs removes and placed in open atmosphere. When I dealt with wideband 15 years ago, we had had to blow out the soot that would build up in them.

By chance did you ever run the car with the sensor in but the gauge not functioning? That will ruin the senor.