# Air/Fuel Ratio Gauge



## omen omega (Aug 26, 2011)

Hello All......


I was wondering what do you want to stay between with an AFR gauge. I am usually between 13.4 and 14.7. Today it was stuck on 14.8 and wouldn't move. then was I pushed the gas it went crazy and spun up to 17.9 and then went blank. I will take this as a one time occurance and ask the question what range is it suppose to be at. My Dodge charger owning neighbor said 13 to 14 and 12 at WOT and that I should use a tuner to adjust it.

SO to the few that have these what do yours sit between, what should it be at WOT and what are areas to not be on...and if I am running rich what the hell does that mean?


----------



## svede1212 (Nov 1, 2005)

What wideband controller do you have? Normal running is done in closed loop meaning the car constantly monitors the exhaust gases and oscillates around 14.7:1 AFR. Depending on mods at WOT you should be 12.6-13:1 and no higher. If forced induction you will be even richer. If you run more than 13 at WOT you risk frying your pistons.


----------



## omen omega (Aug 26, 2011)

AEM. There is no forced induction. It was pinned at 14.8 this morning and did not move at all on my drive, (30 minutes) until I pushed the gas when I was near my exit. Usually it moves from low 14's to 14.8 but today it was pinned. I think it may be malfunctioning. There is a color code and 14.8 is orange, 14.1 is green.


----------



## svede1212 (Nov 1, 2005)

It sounds like it. Like I said the way the car works the car's front O2 sensor reads the AFR state. If the readings is high (lean) it adds a little fuel and the AFR goes slightly below 14.7. Then it reads it as a little low (rich) and it cuts a bit of fuel to get it slightly above 14.7. That repeats itself so on a chart you see a zigzag centered on 14.7. That's called closed loop as it constantly references itself. 

At WOT it ignores the stock O2 sensor and goes to the tables it was tuned at to give the desired AFR, usually around 12.8 for max power. When you go out of WOT it goes back to the front O2 and zigzags. Sounds like your controller (AEM) is bad. Check your wiring. If it was the sensor it usually pegs itself to max or min.


----------



## 8mydust05 (Aug 29, 2011)

Check the sensors and the wires.


----------



## omen omega (Aug 26, 2011)

funny you say that I was touching the wires under the dash last night looking for the radio connector, maybe I messed somthing up...hmm


----------

