how do i wire a air/fuel gauge

[TSIGuy510]

ive search around and wanted a little more info. so i just got a autometer air/fuel gauge and im trying to wire it. i know to somehow connect it the 02 sensor wire from back of the ecu but my question is how would i make that connection and also where would i connect the red and black (power) wires too? the 02 sensor wire from the gauge is purple btw dont know if that helps or not

 

[boosteclipse]

Before wiring it up, you do realize those gauges are mearely a blinking light for our cars. They are not useful for tuning, which is why everyone uses a wideband.

 

[jrohner]

If you're talking about the kind that hooks to the stock narrowband o2 sensor, don't even waste your time. They don't really give you any useful information.

 

[TSIGuy510]

If you're talking about the kind that hooks to the stock narrowband o2 sensor, don't even waste your time. They don't really give you any useful information.

honestly its gotta be better than nothing, i know its crap but i need a rough guide to tune my afc to make sure im not gonna blow up. i understand that its not gonna shout a number out at me but i figure as long as i can use it for a rough tune its gotta be better than not having one at all and tuning blind....

 

[Silver99OZ]

The red wire connects to a 12 V switched source, the black wire is your ground, and the purple wire will need to be tapped into the O2 sensor wire at the ecu. As others have said it will be of no use to you to tune with because it only reads a "narrow" band of voltage. So when the voltage in outside of the band the gauge will give you incorrect readings.

 

[jrohner]

It won't even be a rough guide, sorry. If you want a true 'rough guide', get a cheap volt meter to hook to your o2, at least then you have a number to read. Just realize that the hotter the o2 sensor is, the lower the voltage output (reading leaner).

 

[TSIGuy510]

The red wire connects to a 12 V switched source, the black wire is your ground, and the purple wire will need to be tapped into the O2 sensor wire at the ecu. As others have said it will be of no use to you to tune with because it only reads a "narrow" band of voltage. So when the voltage in outside of the band the gauge will give you incorrect readings.

what does that meen in english? i dont under stand what narrow and wide band meens. hell i dont even know what band meens

 

[boosteclipse]

Maybe to show your o2 cycling in closed loop, all the gauge is going to do is swipe back and forth. When the car goes into open loop that gauge will peg out and hold. It is absolutely useless in tuning, but if you are set on having a gauge light show wire the purple wire to pin # 4. Red goes to a hot activated by the key, black is a ground.

1g ecu pinout:
1G ECU Pinouts

 

[jrohner]

Narrowband is the o2 sensor these cars have stock. They don't give a real AFR reading, where the wideband can give you the actual AFR. The stock ECU uses the o2 at light loads to keep 14.7:1 AFR (to keep the Environmental Protection Agency happy); the o2 sensor is ignored at WOT.

 

[TSIGuy510]

Narrowband is the o2 sensor these cars have stock. They don't give a real AFR reading, where the wideband can give you the actual AFR. The stock ECU uses the o2 at light loads to keep 14.7:1 AFR to keep the Environmental Protection Agency happy.

so does that meen i would have to switch the o2 sensor to a wideband type then?

 

[jrohner]

Get a data logger for tuning, the gauge you are referring to will tell you nothing.

 

[TSIGuy510]

Get a data logger for tuning, the gauge you are referring to will tell you nothing.

yah but that cost $ i dont have the gauge was freee so i was hoping to put it to use but i guess not

 

[boosteclipse]

Not as simple as siply replacing the sensor with a wideband sensor, you also have to have the controller. There a few great widebands, I personally use the aem uego.

 

[Silver99OZ]

what does that meen in english? i dont under stand what narrow and wide band meens. hell i dont even know what band meens

Here is a good link that explains how both work.

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