techmanBDsStang

So I installed my A/F monitor system, and this is what I am seeing. When I start is sits around 14.5, but after a few minutes it starts fluctuating all over the place. When I go WOT, i see the number got around 12.? then it starts fluctuating all over the band as well. I am pretty sure it isn't that my car is going way lean then rich.

I haven't seen anyone else with A/F gauge, but I imagine this is NOT normal. Am I correct in this?

Here are my 2 thoughts.

Either my ground is not grounded correctly. I will get some wire for trouble shooting purposes and start with this and touch certain grounding points.

2nd thought, my sensor is bad. When I installed it, I needed to drive it off the ramps to install the main unit. I know you are not suppose to runthe car with the sensor not powered. I started it, backed off the ramps, and turned the car off quickly. Could this be enough time to actually damage the sensor?

Wally39

Sounds normal to me. Mine runs about 14.6 at idle and runs about 11.5 at wot. If the flow coming out of your exhaust changes quickly it can't keep up.

Simon1

My tuner explained that when the car is not under WOT, the wide band is in "lambda mode" whatever the hell that means. It will fluctuate back and forth from high 13's to 15's just cruising around. Under load or WOT (boost) it will go right down and should give a great reading of the actual A/F.

My tuner also said that some times he has seen the cats cause a "swirling" effect. The air would swirl around in front of the cats and cause the reading to fluctuate a little. Not all cars but some.

techmanBDsStang

Interesting, thanks for the responses.

I should also hook the SCT II up and log the data and see what I get. It is just a pain to do.

ChiDiddy

perfectly normal. your a/f will not be constant when the throttle is being varied (depressed/lifted). at a steady speed, throttle position, ur a/f should remain around the same area. Its when u let off the throttle, u see the a/f go everywhere, first lean, then rich, then slowly back to stoich.

we are talking about a wideband gauge correct?

and, no, u shouldnt be able to damage the sensor that way.

06Saleen3V

An a/f gauge is used to measure the a/f ratio at WOT...thats normal what your describing

modaddict

Ditto to most of the replies. The only time your wideband a/f gauge matters is at WOT and idle. Narrow band a/f gauges are just cool light show mods that have no meaning...

techmanBDsStang

Thanks all, and yes Chididdy, it is a wideband.