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Air/Fuel gauage problems

1K views 11 replies 8 participants last post by  Marks9-3 
#1 ·
so i installed a Air/Fuel guage in my vert and powered it with the same power i use for the boost guage and no the only light i get is full rich. last night it was reading good went into wal mart and now all i get is the full rich light on

help please:confused::confused::confused:
 
#8 ·
Does it just stay there, even on startup? When the sensor warms it will usually climb up the red int the yellow until the sensor starts reading.

Sounds like you don't have signal, not that a narrowband will do anything useful anyways, but it's a fun light show

Want to buy an innovate LC-1? :D

-Chad
 
#9 ·
If you have not spliced it right and if it is not grounded well you can run into all sorts of problems. My advice, dump it if its not a wideband as those things are pretty much junk! And I can admit that I had one in my old spg, and it was only good for adjusting a\f at idle.
 
#10 ·
Eleborating a little on what everyone else said already. Narrowband is 100% useless when you're tuning for performance because the sensor is blind above and below 14.7:1 AFR. Think of it as a switch. Your engine controller uses the information to trim the fuel injection. Under load conditions and especially WOT your fuel control doesn't get any feedback telling the ECU whether the AFR is too lean or too rich...essentially it's blind but it does use that trim information to adjust the amount of fuel that's injected.

You should see it stay pretty steady around idle and at steady-state, no load cruising.

Really, the narrowband open/closed loop setup was a workaround because the wideband sensor technology used to be too expensive but that's not the case anymore. Actually, I think it's safe to assume that all cars in the next few years will come stock with WB O2. There are probably others, but for sure Honda and VW are putting them on the road now.
 
#11 · (Edited)
Here's what a narrowband sensor output looks like.



Lambda 1 (14.7:1) on the X axis represents "perfect" combustion by mass, that is, there's just the right amount of fuel present to burn with just the right amount of air. Below Lambda 1 is rich, meaning there's more fuel than air present, and above is lean more air than fuel.

The Y axis is voltage output. See how they haven't even bothered to use the full 0-1000 mV scale and that it's shortened? 1000 mV equals 1 volt. So the sensor output is 0-1 volts, but because of the sensor response, that 0-1 volts is really mostly useful as a switch to tell you if you're above or below 14.7:1 AFR. Maximum HP for an internal combustion spark ignited (SI) gas engine is going to be found around 12.1-12.6:1.
 
#12 ·
Here's what a narrowband sensor output looks like.

Lambda 1 (14.7:1) on the X axis represents "perfect" combustion by mass, that is, there's just the right amount of fuel present to burn with just the right amount of air. Below Lambda 1 is rich, meaning there's more fuel than air present, and above is lean more air than fuel.

The Y axis is voltage output. See how they haven't even bothered to use the full 0-1000 mV scale and that it's shortened? 1000 mV equals 1 volt. So the sensor output is 0-1 volts, but because of the sensor response, that 0-1 volts is really mostly useful as a switch to tell you if you're above or below 14.7:1 AFR. Maximum HP for an internal combustion spark ignited (SI) gas engine is going to be found around 12.1-12.6:1.
And its for this reason that most WOT runs with a narrowband will yeild a full rich reading on the gauge. That is normal but it doesnt give any tuning help because it could be 10:1 or 7:1 and would read the same on the gauge face.
 
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