R*Speed air/fuel gauge
 

HI I purchased an r speed air fuel meter with the led lights but I dont really know how to interpret what its saying because it jumps all around from lean to rich with no pattern that i can see is this normal or is something wrong please help and yes i followed all the instructions

If it's a narrow band a/f meter it does that when your in normal driving. It's reading the car adjusting the mix. It only really does something when you go into open loop then it will hopefully read rich. A wideband is more expencive but well worth it.

so what does a wideband do thats different and are they installed the same way?

and what do you mean by going into open loop? im new to this stuff

Wideband is much more accurate and uses a different o2 sensor. Do a search here and you will find much information. Open loop is when the ecu quites trying to cruise at a 14.8 a/f ratio and just starts dumping fuel. You can buy a o2 clamp on this web site that will put the ecu into open loop when ever you go into boost. It's a good investment. Just do za search for o2 clamp.

lol for a second there I thought maybe Rspeed released an after market Air Flow meter ... what tim said.

It's working correctly. A narrowband o2 sensor outputs 14.7:1 as .85-.20volts. Since the ECU idles at 14.7:1 AFR it makes small adjustments to make sure the voltage is within that range. So what you see from the sweeping gauge is those adjustments being made, bouncing to each voltage and back to the opposite.

The wideband o2 sensor outputs the o2 readings in the exhaust on a linear scale, so at each voltage increment, it represent a new AFR, when outputted to a gauge, you can see exactly the correct mixture of o2 in the exhaust.

http://techedge.com.au/vehicle/wbo2/fmd/FMD_curve.gif

so lets assume you have 20 LEDS, and they are incrementing in a .5v scale. 1v = 9:1 0v = 18:1

my gauge will show me this with a WBo2:

https://www.miataturbo.net/braineack...nd/gaugewb.jpg

Your's will show you something closer to this:

https://www.miataturbo.net/braineack...nd/gaugenb.JPG

for the ECU to read off and make adjustments, it's fine, for you to tune off, pointless.

so what info can u get off a narrowband that is useful in anyway i only bought it cuz it was 10 bucks and looked and sounded cool but auto wise what can u get from it?

At WOT you'll be able to tell if something is horribly wrong if it's not sweep to rich...otherwise, enjoy the light show ;)

lol thats cool but where can you get a good wideband that isnt to much money??

cheapest will run you $170-180shipped, and you can use your current gauge to display the correct output. (search: innovative motorsports LC-1)


my thoughts are it's worth it's weight in gold.

The LC-1 is my next upgrade for sure.

how can i use my same gauge?????

the lc-1 does not have a gauge, just a few wires comming out of it. you can output a voltage specifically to utilize a narrowband gauge.

http://www.innovatemotorsports.com/r...ntegration.php

so does the lc-1 send the (accurate) NB signal to the gauge and the WB signals to the ecm simultaneously?

yeah, it has two outputs. one for a gauge, one for an ECU. Both can be programmed to whatever scale you need.

you could even remove the oem sensor and send the signal directly to the oem ecu to run off of.

so I could adjust the lc-1 NB output scale to get the gauge to read stoich at say 12:1 afr?


Cool, I learn so much every day on this board.

I guess if I run xede I'll have to run both outputs, adjusted, to the ecm and the xede.

yeah, my gauge only displays between 16:1 and 10:1, I've made myself a little sheet, like what i have above to show me exactly what led is what AFR. This adjusted the scale the gauge displays so I can see smaller increments.

better yet, get an LCD panel, or anything that displays volts, and you'll have a digital readout of the AFR.