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Installing A/F & Vacuum gauges...

  • Thread starter Thread starter Loco5.0
  • Start date Start date May 17, 2005

Loco5.0

5 Year Member
Apr 2, 2005
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May 17, 2005
#1
  • May 17, 2005
  • #1
Wondering how you guys wired up your A/F gauge? Where did you splice into?

For the vacuum gauge, where did you connect the 1/8" nylon tubing?
 
S

Sicarius428

Active Member
Jan 6, 2004
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May 17, 2005
#2
  • May 17, 2005
  • #2
I connected the hose to the B/P on the vacuume tee by the break booster. I wired my gauge lights to the stock gauge fuse so the dimmer will also work.
Kevin
 

flyinghi3

Member
Jan 11, 2003
313
0
17
Manorville, LI
May 17, 2005
#3
  • May 17, 2005
  • #3
on the O2 sensor there is two white wires and one black wire. thats were you hook the A/F gauge up to.

I hooked my boost/vacume gauge on the vacuce tree.
 
S

Sicarius428

Active Member
Jan 6, 2004
2,085
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May 17, 2005
#4
  • May 17, 2005
  • #4
Don't expect too much from the autometer A/F gauge... they are not known for being accurate at all... mine always reads lean.
Kevin
 
J

JT87NAT

New Member
May 16, 2005
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May 17, 2005
#5
  • May 17, 2005
  • #5
Sicarius428 said:
Don't expect too much from the autometer A/F gauge... they are not known for being accurate at all... mine always reads lean.
Kevin
Click to expand...


All the A/F gauge does is provide a nice light show. If you really want to know your A/F ratio go with a Wideband 02 kit, although they cost around 300 they are great if you are doing any kind of tuning. Any vacuum line coming off the intake manifold should work for your Vacuum gauge.
 

Loco5.0

5 Year Member
Apr 2, 2005
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May 17, 2005
#6
  • May 17, 2005
  • #6
flyinghi3 said:
on the O2 sensor there is two white wires and one black wire. thats were you hook the A/F gauge up to.
Click to expand...
Auto meter instructions say to splice into the wire going from the PCM to the o2 sensor plug, not into the actual o2 sensor wire. I haven't looked yet, but is there more than 1 wire going form the PCM to the plug? If so, which is the signal wire?

FYI, your post seems to say splice into all 3 wires. Might wanna edit.
 

Loco5.0

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May 17, 2005
#7
  • May 17, 2005
  • #7
JT87NAT said:
All the A/F gauge does is provide a nice light show. If you really want to know your A/F ratio go with a Wideband 02 kit, although they cost around 300 they are great if you are doing any kind of tuning. Any vacuum line coming off the intake manifold should work for your Vacuum gauge.
Click to expand...
I know, I just need it to fill the hole.
 
J

JT87NAT

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May 17, 2005
#8
  • May 17, 2005
  • #8
Loco5.0 said:
I know, I just need it to fill the hole.
Click to expand...

Yup I have one on my Turbo Supra and thats exactlt why I bought it, just to fill up a hole, I bought a three gauge pillar pod, I have egt gauge, boost gauge, and a/f gauge. I also have an Innovate LM-1 wideband.
 

jrichker

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May 17, 2005
#9
  • May 17, 2005
  • #9
Use 43 (Dark Blue/Lt Geen wire) or pin 29 (Dark Green/Pink wire ) on the computer. Use Wire tap-ins from Radio shack P/N 64-3052. The computer is located under the passenger side kick panel. That keeps you from having to crawl under the car and make a weather proof splice in the wiring. You can use either one, or run a SPDT switch and use both. Then you can use the switch to select which side to view.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/t...91eecPinout.gif

The A/F gauges that use the O2 sensor signal will jump all over the place. The reason is that the O2 sensors "switch" between .2 volt lean and .6 volt rich with a curve that looks like the drop off a high cliff. The curve is almost straight up and down, so the voltage shoots from .2 to .6 and back down . again 2 or more times a second at cruse. You won't get much useful information except when the mixture is extremely lean or extremely rich, there is no middle ground.

AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model cars

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model cars

http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-98 model cars
 

flyinghi3

Member
Jan 11, 2003
313
0
17
Manorville, LI
May 17, 2005
#10
  • May 17, 2005
  • #10
Loco5.0 said:
FYI, your post seems to say splice into all 3 wires. Might wanna edit.
Click to expand...

WOOPS... theres are 3 wires that come off the o2 sensor. 2 white and a black. mine is connected up to the black wire. the black is the signal wire.
 

Loco5.0

5 Year Member
Apr 2, 2005
394
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May 17, 2005
#11
  • May 17, 2005
  • #11
jrichker said:
http://www.veryuseful.com/mustang/t...91eecPinout.gif
Click to expand...
Not working
 

Loco5.0

5 Year Member
Apr 2, 2005
394
6
29
PA
May 21, 2005
#12
  • May 21, 2005
  • #12
jrichker said:
Use 43 (Dark Blue/Lt Geen wire) or pin 29 (Dark Green/Pink wire ) on the computer. Use Wire tap-ins from Radio shack P/N 64-3052. The computer is located under the passenger side kick panel. That keeps you from having to crawl under the car and make a weather proof splice in the wiring. You can use either one, or run a SPDT switch and use both. Then you can use the switch to select which side to view.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/t...91eecPinout.gif

The A/F gauges that use the O2 sensor signal will jump all over the place. The reason is that the O2 sensors "switch" between .2 volt lean and .6 volt rich with a curve that looks like the drop off a high cliff. The curve is almost straight up and down, so the voltage shoots from .2 to .6 and back down . again 2 or more times a second at cruse. You won't get much useful information except when the mixture is extremely lean or extremely rich, there is no middle ground.

AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model cars

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model cars

http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-98 model cars
Click to expand...
I guess I should go by the Autozone diagram since the other one you linked is for 88-91 cars

So I should tap into the red/blk wire (#43) or the gray/lt blue wire (#29)
 

Black1987Stang

Active Member
Aug 22, 2004
1,422
0
37
Jersey Shore
May 21, 2005
#13
  • May 21, 2005
  • #13
yup mine is hooked to the black signal wire for the 02 underneath
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
May 21, 2005
#14
  • May 21, 2005
  • #14
JT87NAT said:
All the A/F gauge does is provide a nice light show.
Click to expand...

I said it before in another post and I'll say it again:

I like my light show!! It's even cooler around Christmas b/c I pop in a Jingle Bells CD and cruise around the neighborhood with my "mobile" lightshow. Here is what my a/f looks like depending on how my motor is running:

Lean
View attachment 514089

Stoich
View attachment 514091

Rich
View attachment 514093

I have a A/F guage b/c I LOVE the light show!!
 
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