Autometer A/F gauge question

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superdart

superdart

Shade Tree Tinker Gnome.....
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OK, I got this Autometer Ultra-Lite Air/fuel gauge free from a friend. My question is, do I HAVE to run the Autometer Oxygen sensor? Or will a Bosch from the parts store work just as well?

I don't feel like paying $92 for a kit from Summit for a heated sensor if I don't have to. I'd like to put in two sensors, one on each bank, with a cutover switch so I can look at either bank, but that's two sensors. I don't feel like buying two kits. I figure if a basic sensor from the local auto store works, it'll probably be a bit cheaper.

Anybody?
Thanks
 
You might have to spend the bucks for the right sensor.Problem 1) is it a 1,2,3,4 wire heated sensor,2) does it show in the paper work you have about how many cross counts it needs per second to operate?3) after market sensors are not as good as OEM,they tend to be slower than the OEM.In most cases they use a GM/AC delco heated sensor.If you can find the right sensor for cheaper great,but if the difference is only 10-15 bucks,get the right one,Mrmopartech
 
Well, I found the installation info online. According to their own paperwork, this gauge can be connected to either thier kit, or an already existing O2 module (either heated or not, diagrams are included for both).

Install file

I would infer that this means it should work with any (?) quality unit. If there isn't really a price difference, yes, I'll spend the few bucks to be sure.
 
Honestly, that guage really won't tell you a whole lot. But it will look really cool, especially at night. I had one in my GN mounted in the A-pillar pod. The ricer dudes loved it.

If you want to get some meaningfull air/fuel ratio data, you will need a wide band oxygen sensor with data logging capability.
 
I agree with Greg. It will only tell which side of a 14.7 ratio you are not at all useful for tuning. I had one on the A-pillar of my Shelby Daytona. When adding more boost to a turbo car they will give you an indication if you are going lean and allow you to get out of it before burning a piston.
 
I am curious about why you think it will be worthless for tuning purposes. You should at least be able to get a good baseline for the cruise, power and idle jettings.
I have my collectors set up with bungs and was planning on doing just what Superdart is talking about. I would spend $200 to avoid 3 days of trial and error tuning ,
not to mention pulling plugs out of hot motors for readings.
 
mbaird said:
I am curious about why you think it will be worthless for tuning purposes. You should at least be able to get a good baseline for the cruise, power and idle jettings.
I have my collectors set up with bungs and was planning on doing just what Superdart is talking about. I would spend $200 to avoid 3 days of trial and error tuning ,
not to mention pulling plugs out of hot motors for readings.
Click to expand...

#1 - If your narrow band O2 sensor is working properly, and the mixture is in the right ballpark for 14.7:1 stoich ratio, all you will see on the gauge is the LED bouncing wildly between rich and lean.

#2 - If the miture is too rich or too lean, then the LED's will go to one end of the scale. The problem is the NB O2 sensor cannot accurately tell you by how much the mixture is too rich or too lean.

#3 - You have absolutely no way to record any readings from the gauge. All you have is the visual indication. Do you want to take a 1/4 mile blast with your eyes glued to a gauge? I don't want to be in the lane next to you if you do.

If you are willing to spend $200 for a NB O2 sensor and a bouncing LED gauge that won't tell you much, go right ahead. But for another $100-$150 you could get a true Wide Band O2 sensor that can provide some very accurate data.
 
Greg, the wild dancing of the gauge is due to the closed loop control of your mixture in a EFI engine.

The issue is that the sensor only has one accurate point which is at the 14.7:1 stoich ratio. The 02 sensor puts out 0-1 volt with 14.7 occuring at .5 volts. Best power ratio for most engines is aroud 12:1 and best economy is around 16:1, the O2 sensor is at it's extremes in range before those numbers are reached.
 
Dave, I agree that the O2 sensor feedback and correction with EFI will cause dancing on the gauge. But the dancing is also caused by fluctuations in timing (spark walk) as well as differences in the mixture from cylinder to cylinder. I can turn off the closed loop O2 feedback on my GN with the custom chip and tuning SW I have, and the A/F gauge will still be dancing.
 
The O2 sensor output would be steady at 7 lights on my Shelby Daytona when it was cold and running in open loop. And, it would be steady a 9 lights when I was at WOT under acceleration (14 psi boost) again open loop. This was typical operation of the Shelby Dodge turbo vehicles.

Never had any experience with other vehicles and how they behave. FWIW, I have been told that the up stream O2 in my 03 Turbo PT Cruiser is a wide band sensor.
 
That's good info on the o2 sensors.
I understand fuel injection just enough to get myself in trouble and did not realize that there were wide and narrow band sensors. I just went back to our shop and asked our lead Acura tech about this . He pretty much said exactly what Greg stated. BTW, this guy knows his stuff on both imports and muscle cars.
 
Well, a few things:

The gauge was FREE. I never really planned to install one originally. But, I figure what the hell, it's free (Ok, maybe not if I have to drop $200 on sensors).

I don't care too much about datalogging capability. This is not a race car. It'll see the track, but not very often. But, your saying a narrow band isn't even good enough for BASIC engine tuning??

Maybe I'll save the money, and put some other gauge in the dash (I have a new custom 3 hole/1 DIN radio plate). I was planning on A/F, Volt and Oil pressure guages. Maybe I'll go another route. Trans temp? Better temp gauage?
 
superdart said:
But, your saying a narrow band isn't even good enough for BASIC engine tuning??
Click to expand...
Well it's not ideal, but you can still get some use out of it. Since the gauge was free, just pick up an aftermarket O2 sensor and install it. You will probably want a heated sensor, especially if you have headers. But what I would recommend for tuning purposes is use a digital voltmeter and read the sensor directly. The digital meter will be easier to read than the LED gauge because it will be averaging the signal and the response is a little bit slower. You want around .45V for light throttle cruising. And up around .65V for WOT acceleration.
 
Heh..maybe I should just mount an LED VDC display on the dash and wire it to the sensor...LOL ..seriously, I'll probably just go with the aftermarket gauge and see what happens. Yes, it'll mostly be for looks....
 
OK, FINE....

I have decided to hell with the A/F gauge, and I'm installing VDO Vision Volt and Temp gauges to match my oil gauge (instead of the other way around).
I decided there is no point to wasting money on a gauge that is just going to look pretty and do me very little good.

I picked a temp gauge, because I question the reliability of the factory temp gauge. Here it is with the VDO oil, and the Autometer A/F and Volt gauges. The Autometers were free, and I'm sure I'll find someone that wants them. (No they are not installed int he pick, just mocked up for reference). I like the black face gauges better anyway.

273700.jpg
 
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