another wiring question

[jdbubb at ix.netcom.com (Dan Bubb)]

Well, this is pretty straight forward. The unit has power and you tapped into the correct wire, so not sure what's up.
I assume your engine has CIS-lambda, so with the engine warm at idle (or cruise) the gauge should fluctuate from rich to lean just like if you were monitoring the frequency valve duty cycle.
Is your frequency valve fluctuating like it's supposed to? If not the O2 sensor is probably bad.
Also, you shouldn't expect too much as far as accuracy from this gauge. It will accurately tell you if you're at stoichiometric or whether you are rich or lean, but it really will give you no idea HOW rich or lean. As an example, if you were running open loop and at 15.5:1 while cruising down the highway (which the engine would be totally happy with) the gauge would indicate dead lean. Very little accuracy on the lean side and not much better on the rich side.
Dan (the other Dan)


----- Original Message ----- 
  From: Dan Smith 
  To: Dan Bubb 
  Sent: Wednesday, May 14, 2003 4:25 PM
  Subject: Re: another wiring question


  I started the engine and let it run for about 5 or more minutes. I figured if it hadn't done anything by then, it wasn't going to. All there was was the brief flash of display when I turned the key. I spliced the o2 wire into the green wire, which runs from the o2 connector to the computer, so I'm pretty sure that's good. I assume my o2 sensor works, but maybe it doesn't, though the car runs fine.

  Dan

  Dan Bubb <jdbubb@ix.netcom.com> wrote:
    If the engine isn't running and the O2 sensor isn't warmed up it's output
    will be 0 V.
    So, if you're just turning on the key the gauge should just sit there and
    look stupid.
    What happens if you run the engine? or did you do that and still get
    nothing?
    Dan

    ----- Original Message -----
    From: "Dan Smith" 
    To: 
    Sent: Wednesday, May 14, 2003 2:29 PM
    Subject: Re: another wiring question


    >
    >
    > Drew Teague wrote:
    > >Ok, I found the green o2 wire and got that all wired up and I wired the
    > >power to the solid black wire. When I turn the key on, the air/fuel gauge
    > >lights up for a second and then goes dead. Did I pick the wrong wire? Do
    I
    > >want the black/yellow one?
    > >
    > >Dan
    >
    > Well, that shouldn't make a difference. The black/yellow lead is for
    wiring
    > high-drain devices like headlights. This circuit is off when the starter
    is
    > engaged, assuring max power (Simpson's reference, haha) to the starter.
    > With the key in the run position (and off position, for that matter), the
    > solid black and black/yellow wire should act identically. Does the unit
    > have three wires total, one each for 12v lead, ground and O2 input?
    >
    > **Drew Teague**
    > Harrisburg, PA
    >
    > '84 8v Rocco -- "Bruise"
    > '85 BMW 318i
    >
    > No, it has 1 wire for o2, 1 wire for to go to the headlights so that it
    illuminates at night (this isn't hooked up yet), 1 ground wire and 1 power
    wire. Could it be that I have to hook it up to the headlights to complete
    the circuit or something?
    >
    > Dan
    >
    >
    >
    > ---------------------------------
    > Do you Yahoo!?
    > The New Yahoo! Search - Faster. Easier. Bingo.
    > _______________________________________________
    > Scirocco-l mailing list
    > Scirocco-l@scirocco.org
    > http://neubayern.net/mailman/listinfo/scirocco-l



------------------------------------------------------------------------------
  Do you Yahoo!?
  The New Yahoo! Search - Faster. Easier. Bingo.