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Fostang or any other EFI gurus, I have a computer question.

  • Thread starter Thread starter 88 Fox GT
  • Start date Start date Oct 1, 2004

88 Fox GT

Active Member
Nov 18, 2002
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Iowa
Oct 1, 2004
#1
  • Oct 1, 2004
  • #1
I bought an A9P computer for my EFI swap. I am wondering, since it's an automatic computer, will it throw off any codes when the transmission ID plugs are not connected to an automatic transmission? Basically what I want to know is will the computer throw a code if it detects that it's not connected to an automatic? I know it will function correctly, but when doing a diagnostics test, I don't want to keep seeing tranny codes coming up or something.

I also heard the A9P has no rev limiter since it's an automatic computer. I don't know why it wouldn't but is this true? Or does it have the regular 6250 RPM rev limiter?

Thanks
 

Glen's 1965 5.0

Founding Member
Feb 5, 2001
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Tomball,Texas
Oct 2, 2004
#2
  • Oct 2, 2004
  • #2
codes

You may see a neutral safety switch code but there is no worry. I have about 5 of them and none effect performance. A custom aftermarket chip and those codes can be turned "Off" if desired.
 

88 Fox GT

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Nov 18, 2002
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Iowa
Oct 2, 2004
#3
  • Oct 2, 2004
  • #3
Ok thanks. Do you know anything about the rev limter?
 

Glen's 1965 5.0

Founding Member
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Tomball,Texas
Oct 3, 2004
#4
  • Oct 3, 2004
  • #4
I think that all Ford ECM's have the same 6250 limit on them.
 

88 Fox GT

Active Member
Nov 18, 2002
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36
Iowa
Oct 3, 2004
#5
  • Oct 3, 2004
  • #5
The TM4O had a 7000 RPM limit, but, yeah I'm going to guess the A9P auto has a 6250 limiter. I'll just have to find out when it's running.
Thanks
 
F

Fostang

Founding Member
May 8, 2002
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Stockton, Ca
Oct 3, 2004
#6
  • Oct 3, 2004
  • #6
also the A3m has a 7K rev limiter thats the chp computer. Almost all ex chp cars came with that one.

Anyways no pre 93 cars don't have a connection with the transmission.

No codes the white pink (or at least most are that color) wire should be connected to the red blue wire which is your neutral safety switch.

Some cars won't start without the computer sensing power through that wire.
 
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