NickD
UltraDork
2/17/18 3:53 p.m.
In my ongoing supercharged 1.8L swap into my 1990 Miata, I am adding an Innovate A/FR gauge and an Auto Meter analog boost gauge. What circuits/wires should I wire into exactly to add these gauges in? Thanks. I'm kinda clueless when it comes to electrical stuff like this.
Well, don't over think it. Both of those gauges probably only need switched 12v, ground, and maybe a dimmer or dash light signal wire. The boost gauge will then have a vac line, and the afr gauge will have it's own wiring to the sensor.
A quick look in a manual for radio or HVAC panel or dashboard wiring diagram should tell you where to grab switched 12v and dimmer. You can tie into an existing ground easy too.
IIRC, white with a red stripe is switched power. They're everywhere.
Rodan
Reader
2/18/18 9:41 a.m.
Keith Tanner said:
IIRC, white with a red stripe is switched power. They're everywhere.
This.
The AFR gauge should come with it's own harness for the wideband sensor, so you're really only looking at power/ground if it's just a monitor. Are you using aftermarket engine management? If so, then you will want it talking to your ECU, which may be a little more involved.
Mechanical boost is pretty straight forward... only wiring should be for illumination. You'll want to tap into the output behind the dimmer switch on the dash, left of the steering column. I used the wiring diagram below when I did my VVT swap... you should be able to find what you're looking for on it. You might want to get a magnafying glass...
1990 Miata wiring diagram
Rodan said:
Keith Tanner said:
IIRC, white with a red stripe is switched power. They're everywhere.
This.
The AFR gauge should come with it's own harness for the wideband sensor, so you're really only looking at power/ground if it's just a monitor. Are you using aftermarket engine management? If so, then you will want it talking to your ECU, which may be a little more involved.
Mechanical boost is pretty straight forward... only wiring should be for illumination. You'll want to tap into the output behind the dimmer switch on the dash, left of the steering column. I used the wiring diagram below when I did my VVT swap... you should be able to find what you're looking for on it. You might want to get a magnafying glass...
1990 Miata wiring diagram
The gauge in a wideband usually contains the controller, so it’s self-contained. Hooking to a ecu is typically a single wire that contains a 0-5v signal.
I think the boost gauge instructions on the FM site include the info you need for hooking into the lighting.
NickD
UltraDork
2/18/18 2:47 p.m.
I'm running MegaSquirt PNP9093
This makes no difference.
Rodan
Reader
2/18/18 4:49 p.m.
The 0-5V signal wire from the wideband controller goes to the O2 sensor input for the MS. Not sure which wire it is on the PnP versions, but your documentation should have that info. There should probably be power and ground for the controller as well.
NickD
UltraDork
2/19/18 5:15 a.m.
In reply to Rodan :
So I just toss the stock O2 sensor?
Rodan
Reader
2/19/18 7:48 a.m.
Yes, the wideband replaces the stock O2 sensor.
NickD
UltraDork
2/19/18 10:20 a.m.
Okay. Like I said, electronic stuff I am not so strong on.