MSD TCM Help!
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Teching In
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MSD TCM Help! Can anyone supply me comprehensive and specific instructions on where to hook up this transmission controller to a GM performance factory harness.
LS 3, 485 hp. 4l70e transmission.
At wits end trying to make this work. Any help would mean the world to me. Thanks
LS 3, 485 hp. 4l70e transmission.
At wits end trying to make this work. Any help would mean the world to me. Thanks
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Joined: Aug 2010
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From: Ann Arbor, MI
Also, is your engine drive-by-wire (DBW) or drive-by-cable? I could not find any success stories about this working with DBW. You might want to call Holley and ask if it is compatible with DBW and how. You might be able to connect the TPS wire to one of the DBW pedal signal wires, but if that connections changes the DBW signal voltage by even a little, it will cause codes and limp mode. (In electrical detail, if TPS wire draws very little current, like 1uA (high impedance), it would not affect the signal voltage. But it it draws even 1 mA (medium impedance) it might lower the signal voltage by enough to cause problems.)
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Joined: Aug 2010
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From: Ann Arbor, MI
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Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
You did not yet mention which ECU you have, if any. If the one from GM Performance, please give us the part number. And also the GM performance harness? If yes, hopefully someone will know which TCMs will work with it.
Several different GM ECU will run that engine; you just have to have the correct ECU connectors on the harness. The E38 and E40 are common ones.
On ebay search for "GM T42 controller" and you will find many vendors who will program the T42 to your VIN and desired transmission type.
I PM'ed you some possibilities.
As I have said elsewhere, I have bought several LS harnesses from ebay vendors and they were all excellent quality. Just need to make sure it has the E40 and T42 connectors and the 4L70E connector.
Several different GM ECU will run that engine; you just have to have the correct ECU connectors on the harness. The E38 and E40 are common ones.
On ebay search for "GM T42 controller" and you will find many vendors who will program the T42 to your VIN and desired transmission type.
I PM'ed you some possibilities.
As I have said elsewhere, I have bought several LS harnesses from ebay vendors and they were all excellent quality. Just need to make sure it has the E40 and T42 connectors and the 4L70E connector.
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