Electrical Ecu 5 speed maf from 92 wont work on 89 maf 5 speed why?

Creomod

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Ok Im posting all these questions that I have,WILL help me bigtime here.I have a 89 5 speed maf that has a lean condition.I want to make sure that the fuel tables/stratgey on my a9l isnt the problem.I want to rule that out so I bought a 92 5 speed maf car to drive .Im not sure what the ecu number is becuse it was rebuit and they changed the ford sticker with the barcode.When I installed it in my 89 the car just turns on and shuts right off.Im assumming it should work beacuse its equvilant I belive Thats just my opinion seeing they are both from maf 5 speed cars.Way differnet years thou.Might anyone have an answer to this one?Any imput would be apprecited
 
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Wayne Waldrep

Before I post a pic, do you have one of yours?
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I hate when people destroy original documentation. I used a 92 5sp computer in my 88gt that I converted to mass air. Still in there to this day with no problems. I'm curious to know the answer. There's a couple guys that know this stuff thoroughly so I'll let them get in here and help.
 
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Creomod

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I hate when people destroy original documentation. I used a 92 5sp computer in my 88gt that I converted to mass air. Still in there to this day with no problems. I'm curious to know the answer. There's a couple guys that know this stuff thoroughly so I'll let them get in here and help.
Thank you it’s soo overwhelming when you have 2 cars that have issues.
 
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Creomod

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Thank you it’s soo overwhelming when you have 2 foxbodys that have issues. I’d like to add in I also have a microsquirt and same thing when I run it as maf it turns off and shuts right off. I can only run sd with the micro but then my engine runs rich 12 to 13 with my a9l runs 20s afr but stays on and ideal good but is too lean
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
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Just for the record, the 92 computer was in a running car that you own? And.... Have you put it back in the 92 and made sure it will still start after not starting the 89? Just building some info for the thread.
 

Creomod

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Just for the record, the 92 computer was in a running car that you own? And.... Have you put it back in the 92 and made sure it will still start after not starting the 89? Just building some info for the thread.
Yes it works just fine on my 92. I’m not running the 92 because I might’ve blown head gasket on that one but yes it works flawlessly
 

jrichker

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Have you dumped the codes on the replacement computer?
Dump codes sticky

Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. Codes may be present even if the CEL (Check Engine Light) isn’t on. You don’t need a code reader or scanner – all you need is a paper clip, or if your lady friend has a hair pin, that will do the job.
I highly suggest that you read it and follow the instructions to dump the codes. http://www.stangnet.com/mustang-forums/threads/how-to-pull-codes-from-eec4.889006/

Computer & interchange information for 5.0 Mustang
Revised 16-Oct-2011 to add O2 sensor harness warnings

The Mass Air computers from 89-93 Mustangs are interchangeable with a few exceptions. Just be sure you use the MAF & MAF sensor from the same series computer. The auto transmission computers use a different start circuit than the manual computers. You can use an auto trans computer in a 5 speed car with no problems or changes. I have done it in my original 89 Mustang GT, and I know it works OK. I would recommend avoiding using a 5 speed computer in an auto trans car due to the possibility of damaging the computer’ internal signal ground circuitry.
The odd duck is the 93 Cobra computer, labeled X3Z which is internally calibrated for 24 lb injectors. Use the MAF & MAF sensor from the X3Z computer to avoid problems with the computer's internal calibration. Try and avoid the 93 Cobra computer if you can.

Some cautions about O2 Sensor harnesses need to be observed to avoid damage to the computer.
Only run a 5 speed trans O2 harness with an A9L. Do not run an Auto O2 sensor harness with an A9L. Doing so will damage the computer’s internal signal ground.
Only run an Auto trans O2 sensor harness with an A9P in a car that has an Auto trans. Using a 5 speed trans O2 sensor harness with an Auto trans will cause no crank problems.

See http://forums.corral.net/forums/general-mustang-tech/1094179-oxygen-sensor- harnesses-manual-auto-differences-year-differences.html for more O2 sensor wiring harness info
If you have a damaged computer with signal ground problems, see the pictures below for help finding and fixing the burnt computer trace.
hash-146a243133771eeba54f17b17d721b1f-jpg.jpg


The fix is some careful soldering of a small jumper wire across the burnt section of copper trace.
20160325_234845-jpg.553347


All the following are mass air unless they say Speed Density
8LD - MANUAL 88 5.0L Mustang Mass Air - California
8LF - Auto 88 5.0L Mustang Mass Air- California
8LG - Auto 88 5.0L Mustang Mass Air- California
A9L - 89-93 5.0L Mustang 5-spd Mass Air
A3M - 93 5.0L Mustang 5-spd Mass Air
A3M1 - 93 5.0L Mustang 5-spd Mass Air
X3Z - 93 5.0L Cobra 5-spd Mass Air internally calibrated for 24 lb injector
A9P - 89-93 5.0L Mustang Auto Mass Air
A9S - 88 5.0L Mustang California Mass Air
C3W - 89-93 5.0L Mustang Auto
DA1 - 87 5.0L Mustang 5-spd Speed Density
J4J1 - 94-95 5.0L SVT Cobra 5-spd
T4M0 - 94-95 5.0L GT Vert 5-spd
U4P0 - 94-95 5.0L GT Auto
W4H0 - 94-95 5.0L GT
ZA0 - 95 Cobra R
D9S - 88 Lincoln LSC Speed Density

Email me a picture of the barcode label and I'll see if I can read it. If you have a smartphone, there may be a app you can download from the Google App Store to read it. See https://play.google.com/store/apps/details?id=com.gamma.scan&hl=en_US&gl=US
 
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Creomod

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Have you dumped the codes on the replacement computer?
Dump codes sticky

Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. Codes may be present even if the CEL (Check Engine Light) isn’t on. You don’t need a code reader or scanner – all you need is a paper clip, or if your lady friend has a hair pin, that will do the job.
I highly suggest that you read it and follow the instructions to dump the codes. http://www.stangnet.com/mustang-forums/threads/how-to-pull-codes-from-eec4.889006/

Computer & interchange information for 5.0 Mustang
Revised 16-Oct-2011 to add O2 sensor harness warnings

The Mass Air computers from 89-93 Mustangs are interchangeable with a few exceptions. Just be sure you use the MAF & MAF sensor from the same series computer. The auto transmission computers use a different start circuit than the manual computers. You can use an auto trans computer in a 5 speed car with no problems or changes. I have done it in my original 89 Mustang GT, and I know it works OK. I would recommend avoiding using a 5 speed computer in an auto trans car due to the possibility of damaging the computer’ internal signal ground circuitry.
The odd duck is the 93 Cobra computer, labeled X3Z which is internally calibrated for 24 lb injectors. Use the MAF & MAF sensor from the X3Z computer to avoid problems with the computer's internal calibration. Try and avoid the 93 Cobra computer if you can.

Some cautions about O2 Sensor harnesses need to be observed to avoid damage to the computer.
Only run a 5 speed trans O2 harness with an A9L. Do not run an Auto O2 sensor harness with an A9L. Doing so will damage the computer’s internal signal ground.
Only run an Auto trans O2 sensor harness with an A9P in a car that has an Auto trans. Using a 5 speed trans O2 sensor harness with an Auto trans will cause no crank problems.

See http://forums.corral.net/forums/general-mustang-tech/1094179-oxygen-sensor- harnesses-manual-auto-differences-year-differences.html for more O2 sensor wiring harness info
If you have a damaged computer with signal ground problems, see the pictures below for help finding and fixing the burnt computer trace.
hash-146a243133771eeba54f17b17d721b1f-jpg.jpg


The fix is some careful soldering of a small jumper wire across the burnt section of copper trace.
20160325_234845-jpg.jpg


All the following are mass air unless they say Speed Density
8LD - MANUAL 88 5.0L Mustang Mass Air - California
8LF - Auto 88 5.0L Mustang Mass Air- California
8LG - Auto 88 5.0L Mustang Mass Air- California
A9L - 89-93 5.0L Mustang 5-spd Mass Air
A3M - 93 5.0L Mustang 5-spd Mass Air
A3M1 - 93 5.0L Mustang 5-spd Mass Air
X3Z - 93 5.0L Cobra 5-spd Mass Air internally calibrated for 24 lb injector
A9P - 89-93 5.0L Mustang Auto Mass Air
A9S - 88 5.0L Mustang California Mass Air
C3W - 89-93 5.0L Mustang Auto
DA1 - 87 5.0L Mustang 5-spd Speed Density
J4J1 - 94-95 5.0L SVT Cobra 5-spd
T4M0 - 94-95 5.0L GT Vert 5-spd
U4P0 - 94-95 5.0L GT Auto
W4H0 - 94-95 5.0L GT
ZA0 - 95 Cobra R
D9S - 88 Lincoln LSC Speed Density

Email me a picture of the barcode label and I'll see if I can read it. If you have a smartphone, there may be a app you can download from the Google App Store to read it. See https://play.google.com/store/apps/details?id=com.gamma.scan&hl=en_US&gl=US
Thanks for the reply soo much!I didnt see it with my other post.As for codes when you asked about dumping codes with the replacemnt do you mean I shouldve scaned for codes even though the car kept turning off with it?Should i install it try again and then run codes while its in the car thats not starting to see what its saying?Its from my 92 but it starts 89 car but shuts right off as if i didnt have the maf sensor connected.So your also suggesting that maybe i should try the maf from the 92 along with the ecu?So try turning it on with its maf becuse i just tryed swapping the ecu nothing else.Question i dont see the answer to it,can i ditch the a9l and run a microsquirt but run it as speed density?Would that ruin my o2sensor harness?Reason I ask is running microsquirt runs car rich and a9l running lean.And in any other car if im running rich whats considered too rich to where it could cause a backfire?If im running 12s 13 on my afr (im assuming not too rich)is that dangerous running it in that area?Im really trying to get it at 14 15 at least but with speed density it runs rich.Id tryied severl times running maf on the micro but same thing turns on shuts right off weird to me.I have a few ecus i also have a da1 i bought for no appernt reason o yes i just read about taking pic im not at home but i will shoot you one tomorrow id really apprectie that
 
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Creomod

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The micro running rich could be many things including an unfinished tune. How much tuning was done on the micro?
No tunning at all I just assumed the msq thats in there was working right and would be something on the mechanical end causing thats just what im assuming but i could be wrong
 

a91what

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The .msq is purposefully enrichened... its not meant to be a plug in and drive, thats way to difficult to get right on a SD setup where most are using non stock parts.. its meant to be a starting point for you to begin tuning.
The micro can be used with MAF btw you just have to do some wiring
 
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Creomod

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The .msq is purposefully enrichened... its not meant to be a plug in and drive, thats way to difficult to get right on a SD setup where most are using non stock parts.. its meant to be a starting point for you to begin tuning.
The micro can be used with MAF btw you just have to do some wiring
The car is a maf already whats other wiring would i have to do?
 

Creomod

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you will need to find the MAF wiring at the 60pin jumper plug and wire it into the micro this mostly consists of some re-pinning
Wow I never knew that it didnt mention in the instrutions,i was just reading the site says that dosent use the maf perfect for boosted applications
 

Creomod

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I usually run both the MAF and the MAP but the map input can be reused for the MAF input
Lol im lost,If you meant the microsquirt map its connected and the maf connector is to it no vaccum line to it and capped off at the tree under intake but im not sure what you mean by repinng :(
 

a91what

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Lol im lost,If you meant the microsquirt map its connected and the maf connector is to it no vaccum line to it and capped off at the tree under intake but im not sure what you mean by repinng :(
The micro has an adapter harness... You re pin the harness so the Maf is connected instead of the map sensor..
 

Creomod

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The micro has an adapter harness... You re pin the harness so the Maf is connected instead of the map sensor.
So I dont have to connect the map sensor?Whereever the microsquirt map sensor pin is at i should put the maf pin in its place?Would I pin the map where the maf was or i wont use it?Thank you sir