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2005 Rubicon automatic Turbo 400 swap ECU question

SledgehammerLJ

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Joined
Jan 6, 2022
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6
Location
Connecticut
Hi all,

I'm in the middle of a AMC Turbo 400 swap in my 05 Stroked Supercharged LJ. Obviously this being a non-electric trans, I need to turn off the automatic functionality. Someone said it could just be left unplugged which doesn't make a lot of sense to me. I've also heard you can flash the auto transmission. It has an HP Tuners tune in it. I've called the tuner several times and he hasn't called me back. Anyone know by chance what the best fix is for this? If I leave this unplugged in the mean time, will I just get a CEL on? Thank you, let me know.
 

Theblkprl1999

The black pearl
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Apr 13, 2022
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UT
You will get a cel. And I assume you need to ground the NSS. So it isn’t in the mix. That may be all you need to do. I haven’t done the swap. Thought about it quite a bit. But a tune/flash should help with drivability if you have any issues. Not sure if it helps
 
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SledgehammerLJ

SledgehammerLJ

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Joined
Jan 6, 2022
Messages
6
Location
Connecticut
Yes we assumed the same on the NSS. I guess to better ask the question, if anyone has flashed these PCM/TCM's is there a toggle to turn off the auto trans function. I know with HP Tuners you can turn off all kinds of things like emissions equipment and select what not to set codes for etc...
 

Irun

Jeep Addict
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Oct 31, 2019
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Virginia
Yes we assumed the same on the NSS. I guess to better ask the question, if anyone has flashed these PCM/TCM's is there a toggle to turn off the auto trans function. I know with HP Tuners you can turn off all kinds of things like emissions equipment and select what not to set codes for etc...
Talk to @Wranglerfix. Mark knows these computers very well and can likely answer your questions, or help you with the ECU. That said, I've not seen any viable automatic swap options for out platform. If there was, more would be ditching the 42RLE.
 
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Theblkprl1999

The black pearl
Supporting Member
Joined
Apr 13, 2022
Messages
38
Location
UT
Talk to @Wranglerfix. Mark knows these computers very well and can likely answer your questions, or help you with the ECU. That said, I've not seen any viable automatic swap options for out platform. If there was, more would be ditching the 42RLE

Exactly why I’m currently doing a v8 swap because there were no local viable options for my cracked 42. Now it’s getting a 5.9 and 46re

But yes wranglerfix or even give b and g Chrysler a call they do a lot with the mopar ecu and swap stuff may be worth a call
 
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