Ok, so I rigged up my brand spanking new Summit Air fuel gauge today and of course took her for a test spin (had to see what my brand spankin new Bosch O2 sensor was doin ) and I noticed some odd behavior.

At idle and anything less than 1/4 throttle or so (no matter what RPM, 1/4 throttle at 4000rpm or 2000rpm) I get NO BARS at all. 0, none, nil. Hm, odd I thought. If I just give it a touch more than 1/4 throttle or so it jumps around like the ECU is in closed loop mode, ok, seems normal, at WOT it's 1-2bars into the rich side, ok, cool...but I was wondering, do all of you w/ these gauges (or any O2 gauge for that matter) have any similar readings? Does the O2 sensor need a higher gas flow to read that it's not getting at lower throttle settings? Do I have a bad ground to the sensor?? This is kinda freakin me out, and I'm really hoping that the ECU is getting a good signal despite that, or it may explain my terrable (albeit better now) gas milage.

Thanks guys,
--matt

 

I have an Autometer gauge, but it does about the same that you are describing so don't worry about it

 

The only time I don't get bars is under decel, I get rich at idle, and I get good cycling or rich at crusing speed, and 1-2 bars rich under WOT

 

Check your ground for your gauge. Make sure it is a good one. I had the same problem and moved the ground to a better location. Now I always have bars lit.

 

One quick question. Is the car fully warm?

When the car is cold the oxygen sensor isn't working properly. They have to be heated up before they read accuratly.

I have an autometer guage in my GSL-SE and at idle I'm 1 bar rich and then it's bounces in the stoich area under normal driving.
Under deceleration it goes a little lean.

Hope this helps.

 

yeah, it acts that way even while letting the car idle at work after the "spirited" drive in....
I'm gonna double check the ground, but since it seems to return good values most of the time I'm not too worried. It's just odd that it's blank while idling and on decel.

tho on decel I can understand, since the ECU cuts fuel to the rear rotor and the O2 sensor is mounted on the rear end of the manifold...

--matt