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Discussion Starter · #1 · (Edited)
I'm looking to get the Autometer gauge and has anyone installed it? how difficult is the install and where does the wire taps into to measure the ratio? link to the install would be a great help!

1. where does the power source come from? does one wire tap into the ground wire and the other to the battery (cruise control, stereo, etc)? I tapped OEM boost controller wire into the stereo.

2. I believe it needs to be connected to the O2 sensor. Is that correct? does the gauge come with the coupling?

Thanks in advance
Tim
 

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I know Autometer AF gauges are just cheap voltmeters..
It uses the Stock O2 sensor,,and that way all you know is that you can achieve approximate AF readings.
Any decent brand AF gauge as Greedy,Defi and other good brands, have their own O2 sensor and that why they are better.
Anyway the Greddy AF gauge is listed 300USD$.
WOW,,thats expensive.
Tuca
 

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dont know for sure,,but i think you have to tap the O2 wire from the ECU.
Thanks
Tuca
 

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i have the autometer Air/Fuel Ratio gauge in my car.... i spliced into the o2 sensor from the ecu... i cant remember which wire it was or if it was the front ot rear sensor... but check out projectwrx.com... that guy has a great write up on it and many other gauge installs.
 

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I installed..and nothing

It was so easy to install it. I hooked up the 12V to my power from my instrument panel (LED overlays), grounded it, brought the signal wire down to the ECu and spliced it in the correct place (B17) and I can't get it to come to life. Nothing happens..its black all the time. What's happening?
 

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You have to hook it up to the 12V power - not the lighting power. Find a constant ignition source.

It will also show completely black when the engine is not running.
 

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nevermind

I got it...those parallel splices are hit and miss..I replaced them with inline splices and now we're good. It lingers in the red for awhile..then jumps to green..almost never goes in the yellow section (stoich). Normal?
 

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bringing this back

Quick question. If I have the PonyExpress CEL fix for the downpipe, will that interfere with the A/F reading? Probably a stupid question, but thought it might be important.

Steve
 

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If you hook up the sensor to the rear O2 signal wire, you'll most likely get an erroneous reading. That is because the rear O2 sensor on WRXs do not supply the same voltage readings that normal narrow-band O2 sensors do. I wired my autometer a/f gauge to this sensor and it would never go past stoich. Then I placed an O2 sensor from a 95 Mustang GT in a port on my DP and wired it up and it works perfect.

I know there are others on here who have had the same problem with rear O2 sensor.

BTW, unless you're at WOT, the a/f gauge is supposed to sweep from lean to rich moderately fast. This shows closed loop mode for the ECU
 

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Another thing. Where can I get an O2 sensor? I don't want to spend a buttload of money but I want an accurate A/F gauge.
 

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Do I need another one of those if I'm catless? Where would I put it?
 

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Blue2004WRX said:
Do I need another one of those if I'm catless? Where would I put it?
Here's what I did...

My TBE has a port by the bellmouth (besides the regular rear O2 sensor port by the midsection) I just slapped an O2 sensor in the bellmouth port and wired the gauge up to it.
 
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