Ok here goes,

I wired my power to the turbo timer, ground to any random bolt to the chassis and the signal wire to the ecu.

Basically I couldn't reach the ecu from where the gauge was so I just used a ground wire to extend it so I can actually reach the ecu.

So far when I turn the key into the ON position and not start it, the gauge lights up.

Its just once I start it, its very dim and I can't see it.
Also, it's always on the lean side. The car idles fine at 850 RPMs.

Could it just be that its a bad ground or a bad 12V and not the signal wire.

 

Did you let it sit there a while? Did you do anything other than idle yet? I've found that until the O2 sensor is up to operating temps, the guage is dim or shows nothing at all. As it starts to warm up, the first lean LEDs start to light, and then it starts reading properly after I've driven a bit and its fully warm. At idle, even when warmed up, the gauge shows pretty lean...at least until my airpump died, now it shows fairly rich at idle.

jds

 

Actually once the car turns on, nothing works or its very dim to see.

And like when I start the car, the lights actually work until the car actually starts.

Thats when it just stays very lean and like very very dim.
I drove it around, waited to warm up but nothing.

Anyone else have any idea?

 

I think your problem is the red wire, it is not conected in a right place maybe, try conecting it directly into the ECU main relay wire.
On the 22 pin plug that goes on the ECU
The wire is Black with white stripe, directly across from the blue wire wit red stripe.
Connector num. is 1B

That may fix your problem, that's how I got my Air/Fuel Ratio gauge wired for 2 years now and it works great.

 

yeah, I don't think you connected it to the right wire, check you connections again.

 

Ok, I just double checked and made sure everything is working and kinda is.

Would a faulty ground be the cause for the gauge to not work properly.

Like if it idles, you don' t even see it, but once i step on the gas it lights up to about stoch and just goes to lean when i let off and it disappears again until i hit the gas.

I KNOW my car is not lean as it backfires from to much gas plus that amazing amount of gas smell when i gas it. They also tuned it at KD.

Could the ground be the problem here or is it something else?

 

Current Situation:

I am 100% the power is correct.
If I hook it up directly to the 02 sensor and not splice it to the ecu, it works fine.

Once I do splice it however, it starts to act funny.

I have a PowerFC and not a stock ECU. Could this be the problem?

I have it spliced now and so far I don't know what to say.

It's just not working right. I mean I can hook it directly to the O2, but then I get this wicked gas smell.

Is it safe to run without it connecting to the ecu?

 

Well, its not necessarily incorrect for the gauge to read lean at idle. That said, when you hook it directly to the sensor and leave the ECU out of the picture, you said it works....how is it different?

I'm not that familiar with the PFC...does it run closed-loop at cruise? I think it can...but if you don't hook it up to the O2 obviously it wont. Not necessarily a big deal. I don't know if the PFC likes to see that for any other reasons however.

Bad grounds can absolutely screw with the operation of a gauge such as this. It might not just be the gauge either...could also be the ECU.

How new is your harness? I had a lot of really tough to diagnose problems that were all cleared up when I replaced my engine wiring harness....no closed loop, lots of backfiring and overly rich conditions, fouled plugs and stalling. New harness...problems gone. Not a cheap or easy solution though, especially if you don't know for a fact it will fix anything.

jds

 

Actually when i said it worked properly I meant that it stays on the rich side cause my car does indeed run rich when idle and when i gas it it becomes a bit stoch, then lean when I decelerate then back to rich when it idles.

 

If I remember correctly, my old K&N A/F gauge that I had on my TII didn't light up at idle. It would really only light up under full throttle and didn't respond well to quick changes in throttle input. Not sure about the FD though.

You might want to post on the PowerFC forum as you're not getting much press here. Maybe it hooks up differently with the PowerFC. **** gets frustrating sometimes don't it...

 

Hmm..., its weird cause once i disconnect it going to the pfc, it works fine. =P.