Progress Thread C3W… A9L… A9P?

t1_5.0

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Hello everyone, I recently bought a 93 gt convertible. I noticed it used to be an automatic by the way it was modified to fit the manual shifter. Today I looked at the ECUand I have a C3W. I thought automatics were A9P and manuals were A9L. Is this something I should change? Is the C3W fully compatible with a manual if that’s what came with it as an automatic or is that something they might have swapped when they changed it to a manual or should I replace it with an A9L?

Thanks in advance everyone!
 
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1988 MANUAL 8LD
1988 AUTO 8LF
1989 MANUAL A9L, A9S
1989 AUTO A9P, A9T
1990-92 MANUAL A9L
1990-92 AUTO A9P
1993 MANUAL A3M
1993 AUTO C3W
1993 COBRA X3Z

You can use the C3W ECU with a manual transmission as long as you use a manual trans O2 harness or rewire the auto trans O2 harness for a manual trans.

Good thread on it here:

 
You can use the C3W ECU with a manual transmission as long as you use a manual trans O2 harness or rewire the auto trans O2 harness for a manual trans.

Actually, he can use the C3W as long as he doens't change any wiring and leaves it configured for the AOD ecu.

If he swapped to the A9L, he would need to repin the O2 sensor harness foe a 93 manual car, and swap to the manual trans harness (or just add the two NGS wires and tap into wiring in the driver's kick panel). That last harness is debatable in terms of how necessary it really is.
 
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Actually, he can use the C3W as long as he doens't change any wiring and leaves it configured for the AOD ecu.

If he swapped to the A9L, he would need to repin the O2 sensor harness foe a 93 manual car, and swap to the manual trans harness (or just add the two NGS wires and tap into wiring in the driver's kick panel). That last harness is debatable in terms of how necessary it really is.
Okay cool, so as long as I keep the automatic O2 sensor harness I shouldn’t have to swap the ECU.
 
Okay cool, so as long as I keep the automatic O2 sensor harness I shouldn’t have to swap the ECU.


If the car is driving fine as is, don't change a thing.


Lets say the ECU fails down the road and you get your hands on a good A9L. That's when you need to pay attention to a few things.
 
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I think all I did was put a jumper in the trans harness because my trans didn't have a neutral safety switch. Otherwise left everything else alone.
 
1988 MANUAL 8LD
1988 AUTO 8LF
1989 MANUAL A9L, A9S
1989 AUTO A9P, A9T
1990-92 MANUAL A9L
1990-92 AUTO A9P
1993 MANUAL A3M
1993 AUTO C3W
1993 COBRA X3Z

You can use the C3W ECU with a manual transmission as long as you use a manual trans O2 harness or rewire the auto trans O2 harness for a manual trans.

Good thread on it here:

You left out the 89 manual convertible A9M. It's a weird one that comes up every once and a while.