For a while now, my Autometer Air/Fuel gauge has had a real wide spectrum. For example, the spectrum would range anywhere from 4 bars wide to almost 10 bars wide. And this would occur only in higher R.P.M.'s. At first I thought that it was related to boost, but now I really think its related to the electrical system. For example, just turning on the rear defroster would make the spectrum 2-3 bars wider.

So, if anyone had any "useful" comments/suggestions, it would be appreciated. Thanks

 

Where are your power and ground wires hooked up?

 

My ground is bolted right to the frame near the fuse box to the left of the foot pedals. The positive wire is attached to some wire under the dash controlled by the ignition. I don't know exactly what positive wire that is though. Why, you think that could be my problem?

 

If it is just hooked up to your stock O2 sensor, then dont worry about it too much. As long as it is not pegged on either the rich or lean side, you are doing as well as you can with that setup. If you really want to tune the car, you need to use a wideband O2 sensor, which can actually tell you what your A/F ratio is, not just whether you are running lean or rich.

 

Hmm, what is a wideband O2 Sensor? Is that something that I could just add to my current sensor, or is it something completely different?

 

Completely different animal.

A 4-wire O2 generates a voltage on its own. A 5-wire wideband needs a controller box in order to do anything useful.

A 4-wire O2 has the response of a light switch....meaning, for the range of a/f ratios before and after 14.7:1 , the voltage is relatively constant.

A 5-wire O2 has a linear response...meaning, there are distinct voltage values that represent particular a/f ratios. This is the reasoning why many people will say that any a/f gauge that uses the stock O2 sensor is junk.

Here is a pic to illustrate:

 

the problem is your ground.

Tap the ECU ground, and it will only show one bar at a time.

 

cool, thanks for the info... ill try tapping the ecu ground first then ill look into the wideband 02