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New Ecu Question

  • Thread starter Thread starter 85rkyboby
  • Start date Start date Sep 27, 2014

85rkyboby

Active Member
Mar 2, 2011
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South ATL
Sep 27, 2014
#1
  • Sep 27, 2014
  • #1
Hey guys, my uncle has a 91 LX fox and his ecu is bad. The car is a manual. What do I need to look for in a new ecu? His ECU # is EECIUSFIMA12A E9ZF12H650-(either H or A)AG Sorry I can't really read his handwriting.

Thanks,
Garrick A.R.
 

Onefine88

Previously 89SSC18
10 Year Member
Aug 3, 2006
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Sep 27, 2014
#2
  • Sep 27, 2014
  • #2
Look for a A9L(which is what he has) or a A9P. The A9P is for an automatic tranny but works fine with the manual.
 
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mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Sep 27, 2014
#3
  • Sep 27, 2014
  • #3
autozone sells them
 
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jrichker

StangNet's favorite TOOL
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Mar 10, 2000
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Dublin GA
Sep 27, 2014
#4
  • Sep 27, 2014
  • #4
The Mass Air computers from 89-93 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.


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
 
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85rkyboby

Active Member
Mar 2, 2011
923
96
39
South ATL
Sep 28, 2014
#5
  • Sep 28, 2014
  • #5
Thanks for the responses. As always @jrichker, very good detailed answer.
 
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