Air Fuel Ratio Gauge Help

all your DIY needs
Post Reply
User avatar
classicdat
Committee Members
Posts: 3260
Joined: Wed Apr 21, 2010 9:59 pm
aka: Vaughan
Location: Datsun Central, Christchurch
Contact:

Air Fuel Ratio Gauge Help

Post by classicdat »

I have just purchased a second hand AutoGauge AFR Stepper Motor gauge, no wiring diagram or anything, pictures attached.
I powered it up, red to 12v and Black to ground, nothing else connected, and it lights up and the needle goes right around.
No matter what else I do that is all that happens, grey to sensor, violet to sensor, grey to 12v, nothing changes, still full rich is displayed.

Any ideas? Not much use currently.

Confession: Is fitted to a VT Commodore, Gen 3 5.7L in to the factory sensor, bit sophisticated for a 1200 on carbs!

First shot shows the 4 wires, Grey, Violet, Black and red
You do not have the required permissions to view the files attached to this post.
Datsuns from A to Zed
User avatar
DJZ
Datsun God
Posts: 2599
Joined: Mon Apr 05, 2010 6:56 pm
Location: Christchurch

Re: Air Fuel Ratio Gauge Help

Post by DJZ »

I'm pretty sure one of the extra wires will be for connecting to the dash lights, I'd suspect it would be the purple one.

How many wires does the oxygen sensor have and do you know which wires are which? There are a couple of different types of O2 sensor but I'd think a Holden would use a standard style one.

I'd be careful about putting 12 volts on the wires as well, most O2 sensors are only 0 - 1V unless it's a wideband sensor, I think they might be 0 - 5V?
Nissan 280ZX
Project thread
Other Nissan 280ZX
Project thread
datsunboy
Datsun God
Posts: 2016
Joined: Fri Jul 18, 2008 10:31 pm
aka: Dan
Location: Christchurch
Contact:

Re: Air Fuel Ratio Gauge Help

Post by datsunboy »

correct....narrowband is 0-1V, wideband is 0-5V
This will surely be a narrowband gauge, and designed to just receive a 0-1V signal from the factory wired O2 sensor.

Some factory sensors are heated, some are not.....both will be narrowband
1969 SSS Nissan Bluebird coupe
1970 Datsun 1600 - CA18DET - Sold!
User avatar
classicdat
Committee Members
Posts: 3260
Joined: Wed Apr 21, 2010 9:59 pm
aka: Vaughan
Location: Datsun Central, Christchurch
Contact:

Re: Air Fuel Ratio Gauge Help

Post by classicdat »

Thanx Guys, yeah only connected voltage to gauge. Car is running LPG so am using the wire they took the O2 signal off for that. But connecting it doesn't matter, still reads full rich.
Datsuns from A to Zed
datsunboy
Datsun God
Posts: 2016
Joined: Fri Jul 18, 2008 10:31 pm
aka: Dan
Location: Christchurch
Contact:

Re: Air Fuel Ratio Gauge Help

Post by datsunboy »

I think that this is the instructions for your gauge.....or very similar.

So violet to dash lights.

the White (or grey in your case) will be the sensor wire.....and should be 0-1V only.

Wire it up like that, and start the car up for 5mins, and if it doesnt change then I'd take a guess that the gauge is poked
1969 SSS Nissan Bluebird coupe
1970 Datsun 1600 - CA18DET - Sold!
User avatar
classicdat
Committee Members
Posts: 3260
Joined: Wed Apr 21, 2010 9:59 pm
aka: Vaughan
Location: Datsun Central, Christchurch
Contact:

Re: Air Fuel Ratio Gauge Help

Post by classicdat »

I fear you are right Dan. Thanx, but not really what I wanted to hear.
Datsuns from A to Zed
User avatar
160jsss
Financial Member
Posts: 418
Joined: Sun Aug 03, 2008 7:41 pm
Location: Chch
Location: Kirwee

Re: Air Fuel Ratio Gauge Help

Post by 160jsss »

you say it's running on lpg that will give you different readings ?
Violet - ??????
Post Reply