How To: Air/Fuel Ratio Gauge Install

[mattybo]

what are the pros/cons of connecting the wire at the 1st o2 sensor vs. ecu?

Why would you ever run wire through your firewall and do all that extra work if you can simply tap into the wire running from the ecu? There must be a reason?

 

[LapisBlueProteg]

i think u get a better reading at the o2 and it took like 2 mins for the fire wall!

 

[Notorious]

the reading at the 02 sensor and the ecu are the same. Since that wire connects to the ecu, but like chris said, takes less time to run it through the firewall than to pull apart the interior and get to the ecu.

 

[Mark94]

Anyone figure out why a few people didn't get any readings with the gauge connected to the ECU?

I'm planning on going this route but want to make sure it works before I do it.

Thanks!

Mark

 

[LapisBlueProteg]

now i have a check eng light on not sure if its because of the a/f gauge not getting a reading!
any help! plzzzzzzzzzzz

 

[benbike]

now i have a check eng light on not sure if its because of the a/f gauge not getting a reading!
any help! plzzzzzzzzzzz

It happened to me too, disconect the battery (negative)..It worked for me

 

[mazdaspeed75]

I installed a venom air fuel gauge and it show rich @ 9psi all the way to redline in every gear . How accurate are they Are they accurate enough to up the boost alittle more with the readings i got . Just wanted to get whta you guys thought i will eventally get a wbo2 but i trade my old whey protein for this meter so i had no out of pockets exspence and the meter was like 90.00 it was brand new . Any info about accuracy would be apprecaited

 

[changedman]

no, they arent very accurate. you'd want a wideband O2 sensor.

 

[mazdaspeed75]

So dont trust it at all . Yea i wnat the aem wbo2 . You may have some business down the road I wnat to build the motor down the road .

 

[celdridge]

where should i tap in for the constant 12v?

Cigarette lighter is perfect.

 

[noclue119]

How many wires do u guys have


I have
Red - 12 v ignation - i guess the cigeratte lighter?
White - Dash lighting - so the dimmer blue/white?
black - ground - green/black wire on the dimmer
violet - #60 on ECU right

Does that sound right u guys?


Also can i use the same 12v ignation on the cigeratte lighter to power all my gauges? Boost, oil pressure and A/F?

 

[Matthew]

shouldnt be a problem. mine are hooked up directly under the steering column or to the radio power.

 

[celdridge]

How many wires do u guys have


I have
Red - 12 v ignation - i guess the cigeratte lighter?
White - Dash lighting - so the dimmer blue/white?
black - ground - green/black wire on the dimmer
violet - #60 on ECU right

Does that sound right u guys?


Also can i use the same 12v ignation on the cigeratte lighter to power all my gauges? Boost, oil pressure and A/F?

You will have 4 wires if you have the C2 Series ... like i do. Most of the others will only have 3 because they dont have a wire for illumination. All your information above is correct. Make sure you fuse your 12v wires ... just in case.

 

[noclue119]

You will have 4 wires if you have the C2 Series ... like i do. Most of the others will only have 3 because they dont have a wire for illumination. All your information above is correct. Make sure you fuse your 12v wires ... just in case.

ya i was goign to to into the cigerrtte lighter for the 12 v constant on the a/f

then i was going to wire the Dash lighting + 2 additional gauge lights to the dimmer's blue/white and green/black

 

[SP5]

shouldnt be a problem. mine are hooked up directly under the steering column or to the radio power.

So let me get this straight. Once I've hooked up the standard wires, i.e., Red - 12 v ignition, White - Dash lighting, and Black - ground. The only other connection is Violet - by tapping the correct O2 sensor wire near manifold (assuming I don't want to connect it to the ECU wire) and running it through the firewall, correct?

SP5

 

[celdridge]

So let me get this straight. Once I've hooked up the standard wires, i.e., Red - 12 v ignition, White - Dash lighting, and Black - ground. The only other connection is Violet - by tapping the correct O2 sensor wire near manifold (assuming I don't want to connect it to the ECU wire) and running it through the firewall, correct?

SP5

Yep .. thats it.

 

[SP5]

So what's the best place to route the wires so that they are out of the way and not visible? Where do you route the wires from the gauge - down the pillar and then where?

SP5

 

[DrummerJim50]

LinuxRacr: can you repost the 1st picture that shows the ECU - it doesn't show up.

 

[LinuxRacr]

That picture was hosted by flyinprotege.com which no longer exists. Time to find another picture.

 

[SP5]

I have a P5 and I'm going to install an A/F Ratio Defi gauge. These are the wires that it came with and the connections I plan to make based on the how-to's I found:

White (Illumination) - Blue/White wire on dimmer switch
Black (Ground) - Green/Black wire on dimmer switch
Orange (12V Ignition) - Red/Black wire off ignition wires?
Red (12V Battery) - Positive Battery or Cigarette Lighter?
Pink (O2 Sensor) - Pink/Blue wire on underhood O2 connector

Are these connections correct? Are there better/easier alternative connections for any of them, specifically the Orange and Red wires?

SP5
(group)