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MAF Converted. Yeah, But now a bit of a Idle Issue.

  • Thread starter Thread starter Manewaymja2
  • Start date Start date Apr 6, 2009

Manewaymja2

Member
Feb 11, 2009
245
2
19
Apr 6, 2009
#1
  • Apr 6, 2009
  • #1
Hi guys Thanks to All who Help me Out with the S/D to MAF Conversion, Went great . Started car and as expected the Idle was a bit up/down between 700 /900 RPM. I know it needs to relearn Idle, so i let idle for about 30 Mins and same thing so i took it for a drive and she drove well No stalls just same idle when sitting in traffic. So leads me to believe that maybe i dont need to be driving around with my Autolites gaped .25 on Normal basis maybe just when spraying.

What do you guys Think? can it be the plugs.

Thanks Matt
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
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Massachusetts
Apr 6, 2009
#2
  • Apr 6, 2009
  • #2
Did you just use the 4-wires from the MAF for the conversion or did you also tap into the VSS??
 

jrichker

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Mar 10, 2000
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Dublin GA
Apr 6, 2009
#3
  • Apr 6, 2009
  • #3
See the "Surging Idle Checklist for help with all your idle/stall problems. Everything you need to find and fix idle problems is in there.

The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 

strtrcr50

New Member
Jun 21, 2006
0
4
0
Previously from Dirty Jerzey exit 7a
Apr 6, 2009
#4
  • Apr 6, 2009
  • #4
When you converted, what processor and harness did you use? Is the car stick or 5 speed?
 

Manewaymja2

Member
Feb 11, 2009
245
2
19
Apr 7, 2009
#5
  • Apr 7, 2009
  • #5
Mustang5L5: Conected the 4 Wires for the MAF along with a wire from the relay under the drivers seat and two wires from the driverside kick panel as instructions
(MAF - Mustang Mass Air Conversion - StangNet - The Mustang Network)

Strtrcr50: Stick Shift, the harness is a 89 Mustang GT complete Harness that i removed the MAF wiring from and a A9T EEC-IV MAF for Auto. Bought the kit from a Guy on ebay complete. But like i said instead of running the intire harness for the car i just removed the MAF harness wiring and completed as per instructions.

jrichker: Will look into the Surging idle Checklist today

Thanks Guys.
Matt
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,945
224
Massachusetts
Apr 7, 2009
#6
  • Apr 7, 2009
  • #6
Ok so you did it the "right" way.

I'd go over jrichker's checklist. Also, does the car toss any codes?
 

strtrcr50

New Member
Jun 21, 2006
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4
0
Previously from Dirty Jerzey exit 7a
Apr 7, 2009
#7
  • Apr 7, 2009
  • #7
Manewaymja2 said:
Strtrcr50: Stick Shift, the harness is a 89 Mustang GT complete Harness that i removed the MAF wiring from and a A9T EEC-IV MAF for Auto. Bought the kit from a Guy on ebay complete. But like i said instead of running the intire harness for the car i just removed the MAF harness wiring and completed as per instructions.
Click to expand...

I had similar problems converting from speed density to a a9p with an automatic harness. In my case, pin 30 which is a signal return loopback was on a different pin on the o2 harness under the mass air sensor. Because I was using a automatic harness and computer, I had to move a pin from one spot to another. I can't find the post with the diagram, but if you look under the mass air sensor, you'll see a connector. When you look at the side that goes into the body/under the car, you will see a wire that loops right back around. You will also see a dummy plug in the harness on the body side. That wire moves to the other plug.

By the way, the harness I'm referring to wasn't changed..
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,945
224
Massachusetts
Apr 7, 2009
#8
  • Apr 7, 2009
  • #8
Damn, all this stuff to remember when i do my MA conversion
 

-86GTStang

Member
Dec 27, 2003
165
0
16
Norway, Scandinavia
Apr 7, 2009
#9
  • Apr 7, 2009
  • #9
If all this is ok, try to rotate the MAF a little, clockvise or counterclockvise.
I had to do this when I installed my 73mmProM and cold air kit.
Do you have the Ford MAF or ? What kind of air filter/box?
 

Manewaymja2

Member
Feb 11, 2009
245
2
19
Apr 7, 2009
#10
  • Apr 7, 2009
  • #10
Have a Ford MAF Now but will be changing to 24lb calibrated C&L shortly.

But im going to do the Pin switch Today and see what Happens

Code:
I had similar problems converting from speed density to a a9p with an automatic harness. In my case, pin 30 which is a signal return loopback was on a different pin on the o2 harness under the mass air sensor. Because I was using a automatic harness and computer, I had to move a pin from one spot to another. I can't find the post with the diagram, but if you look under the mass air sensor, you'll see a connector. When you look at the side that goes into the body/under the car, you will see a wire that loops right back around. You will also see a dummy plug in the harness on the body side. That wire moves to the other plug.

Ill see what happens then get back, but for sure i did not do that step.
 

Manewaymja2

Member
Feb 11, 2009
245
2
19
Jun 17, 2009
#11
  • Jun 17, 2009
  • #11
Hey there Strtrcr50, I have looked at the Plug under the MAF meter and yes i traced the wire under the Car where there is a similiar plug. Is that where i do the wire switch you spoke of (When you look at the side that goes into the body/under the car, you will see a wire that loops right back around. You will also see a dummy plug in the harness on the body side. That wire moves to the other plug. By the way, the harness I'm referring to wasn't changed)or do i do that right at the plug under the MAF meter. Help Please.

Thanks Matt
 
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