Date: Mon, 10 Nov 1997 22:17:45 -0500
From: Rob Robinette I asked this question a couple of weeks ago and didn't get an answer so I
dug out the Shop Manual while installing an HKS FCON and looked for the
oxygen sensor wire at the ECU. I wanted to tap into the O2 sensor at the
ECU for an air/fuel meter. The O2 sensor wire is a solid black wire on the
only 16 conductor ECU connector. The Shop Manual calls it wire 3C. When
viewing the connector from the end that the wires from the car run into it
and with the locking clip pointing up, it is the second wire from the right
on the top row (only black wire on the connector). I put a wire tap that
accepts a blade type male connector on wire 3C so I could easily remove the
air/fuel gauge O2 wire.
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Date: Sun, 7 Dec 1997 10:05:27 -0600 On my Halmeter 15-LED air-to-fuel gauge, the only times I can get it to
stabilize are at idle, WOT, and a VERY consistent throttle input. At idle,
your meter should read somewhere between 14.7 and 12.0 (RICH), depending on
how your car is tuned. But on WOT, the meter should read near all the way
rich. During cruising, the reading fluctuates very rapidly from 13.x to
16.x. Well, that's how my A/F meter functions, anyhow.
_________________
Date: Sun, 7 Dec 1997 11:13:14 -0500 >At idle, no lights are lit. At WOT, they're all lit. If I Sounds about right. Since the voltage will vary from about
.1 (extreme lean) during closed loop at cruise, to about
.88 at the richest conditions (hopefully towards WOT), as
well as idle (with no airpump). The trick is to monitor the
A/F during WOT operations across the performance range,
assuring that it doesn't lean out.
_________________
Date: Tue, 20 Jan 1998 00:24:13 +0000 Just installed my Cyberdyne A/F gauge this last weekend. While I
was at it I measured the voltages corresponding to each LED. This
is what I got from lean to rich:
I did not get a voltage for the final red LED (rich). Given the
trend I would expect it to be around 0.97 v.
My multimeter is rated
for +/- 0.5% accuracy, so the third digit in the above values should
not be considered accurate. Also this is for my sample, others may
get different values. With Cyberdyne's price, I'm not sure how good
their quality control is.
As this shows, the unit does not have
enough resolution in the area of interest (only 2 LEDs covering 0.78
to 0.88 volts) to be very useful for tuning, but can provide an
indication of going too lean.
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From: "John Wise"
From: rotary@mediaone.net (Carlos Iglesias)
>pop the throttle while sitting still, they'll all light up
>then go out, tracking the RPMs.
>
>Is this normal? The gauge rarely, if ever, stabilizes at
>14.7. Usually it's off either end of the scale.
From: cscott@ghg.net (Chris Scott)
red 0.096 v
red 0.196 v
yellow 0.295 v
yellow 0.393 v
green 0.487 v
green 0.588 v
yellow 0.685 v
yellow 0.783 v
red 0.878 v
