oz968

Looking for some advice on setting up an air/ fuel gauge utilising the existing oxygen sensor (O2) in the 968.
Looking at the "destructions" online it shows a light trigger, + power, - earth and signal wire.
The signal wire shows as coming off the O2 sensor wiring to ECU. So possibly T' into the signal wire at the ECU.???
Has anyone fitted up a gauge on a forced induction set up or can some one indicate the wiring fro the ECU and possibly the O2 sensor
I didn't want to have to run a new O2 sensor dedicated to the gauge.
Peter

thomasmryan

Post a picture of your schematic. Most oxygen sensors have a high and low state between 0 and 1 volt. An A/F gauge uses a different type sensor with variable output. You may need a kit that gives you a a/f read out plus the normal output (high/low) that the DME wants to see.

Paul Waterloo

If you are wanting to put an A/F gauge in due to adding forced induction, you don't use the OEM O2 sensor, you need to purchase an O2 wide band kit/assembly. You drill a hole in the exhaust, weld in a bung and then put in a wide band O2 sensor. The sensor for the fuel injection system is a narrow band sensor.

There are many kits out there. Here is mine on a 3" exhaust on my 951.

oz968

Paul
that seems to be the constant direction taken.
thank you for the advice and pics
I will have to drop the exhaust and get a bung welded in
Do we run a cat on the 968 ?

Paul Waterloo

FYI, I did not have to have the exhaust dropped to drill and weld, I would contact a speed shop or dyno shop in your area, they did it in no time right before I had the car tuned for the first time.

Jfrahm

I see most widebands also have a narrowband outlet, can that be used to feed the ECU?

I have a narrowband / gauge in my supercharged 928 and all it really does is show me if the sensor is dithering.

oz968

Heya Joel
I am ready to fire the machine and getting last minute fuelling sorted.
Once I get your old system running correctly I am thinking ahead to using a bit more boost so will want to accurately know what's going on
So am thinking that I will bite the bullet and go WB and run an independent gauge and not "muck" around with the factory ECU feed.
This makes sense to me after having done a bit of homework.
I must thank you and Carl for your guidance and ongoing support through this process.
Peter