I just put in a new air fuel gauge (autometer). I hooked it up to the stock o2 sensor and while in part throttle driving, the gauge jumps around a lot. I know that the ecm is constantly adding and subtracting fuel which is the cause for the bouncing meter.

My question is if i were to put a second o2 sensor into my exhaust on the opposite side, then hook the meter up to the 02 sensor that is not connected to the ecm. Will my meter constantly bounce around during part throttle since the second o2 sensor is not connected to the emc? I think it will not matter becasue the ecm is adding and subtracting fuel from the car and it will still be seen reguardless what o2 sensor i use?

 

Yep.

The gauge is reading the sensor, not the ECM.

The Autometer A/F gauge is eye-candy as far as I'm concerned. I had one for a couple weeks and sent it back because the gauge was just way too accurate for the crap O² sensors found in thirdgens and a waste of money.

 

a buddy of mine has a 86 TT Z with a carb on it. his is very steady. He does not have a EMC, thus the reason his gauge is not bouncing around during part throttle driving. I was using my A/F meter to watch my WOT driving and was hoping for some part throttle stuff too. Outside of eye candy, wot is all its good for

 

It's actually not even any good for WOT because of the O² sensor's inaccuracy outside of a narrow band around 14.7:1 (hence "narrowband O² sensor").

 

What Jza said. You cannot tune WOT even remotely accurately using anything based off the stock O2. All it is good for is seeing if you are grossly rich or lean. Example. Last weekend i helped a guy with a big cam and a HSR to get rid of a bog he had. Just watching the O2 ona scan tool, it was obivous it needed way more pump shot because whenever he hit the gas the O2s dropped to single digits. So it was obviously going way lean. but other than that, the O2 is useless to actually fine tune it.

 

Currenty, I"m running it off of my primary o2 sensor, however, I heard that the 4 wire honda o2 sensors are pretty good. I plan to put the secnod 02 sensor in for some tunning issues when i put my supercharger back on. I figure I can look at the meter and change my fmu ratio from 4/1 to 10/1 and see if there is much difference? If not, guess it's eye candy.