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Ecu Help!! 8ld Vs. A9l

  • Thread starter Thread starter GT Foxbody Man
  • Start date Start date May 31, 2012

GT Foxbody Man

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May 29, 2012
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May 31, 2012
#1
  • May 31, 2012
  • #1
Ok I fried my ecu which is a 8LD.... Trying to find another 8LD is like trying to find a needle in a haystack, its just not working for me!!!lol I have a 1988 stang vert 5.0 gt 302ci, Can I use a A9L in place of the 8LD? the reason I ask is because I can find a A9L just about everywhere!!
 

GT Foxbody Man

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May 29, 2012
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May 31, 2012
#2
  • May 31, 2012
  • #2
Oh and also to add, Ive been up and down the wireing diagrams, check for voltage everywhere and im good... I ran a self test under the hood straight outta the book and applied power where it wasnt supposed to be.. I got a ecu and tried on my car and it started right up, but its not the correct one for my car!!
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
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Jun 1, 2012
#3
  • Jun 1, 2012
  • #3
Is that speed density? I have an 88 computer that I took out for a Maf setup..
 

jrichker

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#4
  • Jun 1, 2012
  • #4
GT Foxbody Man said:
Ok I fried my ecu which is a 8LD.... Trying to find another 8LD is like trying to find a needle in a haystack, its just not working for me!!!lol I have a 1988 stang vert 5.0 gt 302ci, Can I use a A9L in place of the 8LD? the reason I ask is because I can find a A9L just about everywhere!!
Click to expand...
The 8LD is a speed Density computer, A9L is a Mass Air computer. The wiring and function are not the same. Having said that, the A9L can be used to upgrade your car to Mass Air.

MASS air conversion instructions from http://www.stangnet.com/tech/maf/massairconversion.html FREE
A9L (5 Speed) computer from junkyard $100-$150
A9P (Auto or in a pinch, it will work in a 5 Speed car) computer from junkyard $100-$150
70MM MAF from 94-95 Mustang GT - $40-$70
MASS Air wiring harness kit $30-$85

The whole thing is probably less than $300 using junkyard parts.

A9L computers are 5 speed only
A9P computers are automatic, but will work with a 5 speed.

The conversion harness seems to work well for most folks. It avoids the compatibility problems in using a harness from the junkyard. Simple and cheap, actually less work that swapping the wiring harness.
Conversion Harness kits & parts
http://www.mass-air.com/
http://oldfuelinjection.com/index.php?p=54

If the idea of moving & soldering wires scares you, here's a list of compatible Mass Air wiring harnesses.

Copied from bbunt302
Just for reference, here's a list of all the compatible years:

89 harness should work for 86-89 as long as you're using mass air.
90 harness will only work in a 90. (B/c of air bags and dual dash connectors)
91 through early 92 harnesses should be compatible (single dash connector, fuel pump relay under driver's seat)
Late 92 through 93 harnesses should be compatible (single dash connector, fuel pump relay under the hood)

Larger MAF to go with Mass Air conversion:
94-95 Mustang GT MAF - $40-$100. It is 70 MM instead of the stock 55 MM on regular stangs built prior to 94. It uses a slip on duct on the side that goes to the throttle body and a 4 bolt flange on the other. You need a flange adapter to fit the stock slip on air ducting that goes to the air box. Wiring plugs right in with no changes. *1 *2

*1.) Metal flange adapter http://www.kustomz.com/cat3.html Buy the TR70 for $44.95. Or spend some time on eBay looking for one that may fit.
Try AutoZone and ask for 81413 - Spectre / 3 in. Aluminum Intake Mass Air Flow Sensor Adapter at $12.00. You may have to order it online.

*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,
Evidently the –A1A, -A2A, AA, etc. on the end of the part number is a minor variant that did not change the operating specs. You should be able to ignore it and have everything work good.

Also see www.forfuelinjection.com for help with the harness parts http://rjminjectiontech.com/?p=10, and connector pins, http://rjminjectiontech.com/?p=11
 

GT Foxbody Man

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Fort Irwin, CA
Jun 1, 2012
#5
  • Jun 1, 2012
  • #5
Thats funny cause I have the MAF setup under the hood, it ran great with an 8LD..
 

Blown88GT

Founding Member
Nov 13, 1999
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Jun 1, 2012
#6
  • Jun 1, 2012
  • #6
GT Foxbody Man said:
Thats funny cause I have the MAF setup under the hood, it ran great with an 8LD..
Click to expand...
That's because it is NOT a speed density EEC
Too much bogus info being given out here. A little research effort would avoid this.
http://oldfuelinjection.com/?p=17
8LD is indeed an EEC-IV for a MAF equipped CA manual transmission vehicle.
A9S is another one, don't know what the difference is but that's the one that came with the Ford Motorsport Mass Air Conversion kit I used to have.
A9L is probably the most common MAF EEC.
BTW, I still have my SD EEC & it's a DA1.
'87 Calif Mustangs may have been SD; '88's were MAF in Calif only. '89 50 States were MAF.
 

Noobz347

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Jun 2, 2012
#7
  • Jun 2, 2012
  • #7
Blown88GT said:
That's because it is NOT a speed density EEC
Too much bogus info being given out here. A little research effort would avoid this.
http://oldfuelinjection.com/?p=17
8LD is indeed an EEC-IV for a MAF equipped CA manual transmission vehicle.
A9S is another one, don't know what the difference is but that's the one that came with the Ford Motorsport Mass Air Conversion kit I used to have.
A9L is probably the most common MAF EEC.
BTW, I still have my SD EEC & it's a DA1.
'87 Calif Mustangs may have been SD; '88's were MAF in Calif only. '89 50 States were MAF.
Click to expand...


That's not a fair statement. Had YOU done a little research, you would have seen that this OP has had two or three other threads going concerning this same issue (I know this because I've closed and/or deleted them because the various pieces are confusing). Bits and pieces of relevant information has been spread over those threads and folks have been attempting to help this member with his current problem.

What's more, this is the VERY purpose of this forum. If there was one single dude who had all the answers then it wouldn't exist.

It's good that you had a link to help the OP answer his question but I'll tell ya... The folks that have posted responses in this thread so far are very knowledgeable men and have helped a COUNTLESS number of folks in this forum.
 

jrichker

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Jun 3, 2012
#8
  • Jun 3, 2012
  • #8
Blown88GT said:
That's because it is NOT a speed density EEC
Too much bogus info being given out here. A little research effort would avoid this.
http://oldfuelinjection.com/?p=17
8LD is indeed an EEC-IV for a MAF equipped CA manual transmission vehicle.
A9S is another one, don't know what the difference is but that's the one that came with the Ford Motorsport Mass Air Conversion kit I used to have.
A9L is probably the most common MAF EEC.
BTW, I still have my SD EEC & it's a DA1.
'87 Calif Mustangs may have been SD; '88's were MAF in Calif only. '89 50 States were MAF.
Click to expand...
Thanks for the heads up. I will update my list of computer types.
 

GT Foxbody Man

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May 29, 2012
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Fort Irwin, CA
Jun 4, 2012
#9
  • Jun 4, 2012
  • #9
Well thank you guys for the help!! I bought a A9L, plugged it in and Bam the car runs great!!
 

Noobz347

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#10
  • Jun 4, 2012
  • #10
GT Foxbody Man said:
Well thank you guys for the help!! I bought a A9L, plugged it in and Bam the car runs great!!
Click to expand...

Glad to hear you're rollin' again.
 

GT Foxbody Man

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Fort Irwin, CA
Jun 9, 2012
#11
  • Jun 9, 2012
  • #11
Why thank you!!
 
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