T42 OS wrong for my setup?
Thread Starter
Launching!
Joined: Jan 2009
Posts: 241
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From: Mead, WA
T42 OS wrong for my setup? Donor - 08 Sierra 4x4 5.3L/4L60E into a 04 Jeep Wrangler
tcm 24239927
I have been fighting this problem since the install and I believe I have it down to the TCM.
Problem is:
I have no WOT/partial throttle kick downs and it shifts with no regard to the shift tables in the tune. By the time I am at about 20 mph, the trans is already in 4th gear. WOT will not cause it to downshift, moving the selector on the console will. And this doesn't matter if I start out slowly or WOT. When coming to a stop, the trans will down shift.
Through HPTuners, I can command 1st, 2nd, 3rd but not 4th while at a resting stop. If I am driving down the road, I can not command any change.
Through HPTuners the speedo is only off a few MPH - ~2 at 75 mph, GPS verified as well I have an Autometer programmable speedo that is accurate.
There have been a few occasions where the trans will shift correctly, but it's very far between - 5? times in 3500 miles. I have not been able to duplicate the condition that gets it to shift correctly. But the only time it will, is when I have had HPTuners plugged in.
My files are too big to attach, so if you need to see a log or my tune PM me with your email addy and I'll send it over.
Thanks!!
tcm 24239927
I have been fighting this problem since the install and I believe I have it down to the TCM.
Problem is:
I have no WOT/partial throttle kick downs and it shifts with no regard to the shift tables in the tune. By the time I am at about 20 mph, the trans is already in 4th gear. WOT will not cause it to downshift, moving the selector on the console will. And this doesn't matter if I start out slowly or WOT. When coming to a stop, the trans will down shift.
Through HPTuners, I can command 1st, 2nd, 3rd but not 4th while at a resting stop. If I am driving down the road, I can not command any change.
Through HPTuners the speedo is only off a few MPH - ~2 at 75 mph, GPS verified as well I have an Autometer programmable speedo that is accurate.
There have been a few occasions where the trans will shift correctly, but it's very far between - 5? times in 3500 miles. I have not been able to duplicate the condition that gets it to shift correctly. But the only time it will, is when I have had HPTuners plugged in.
My files are too big to attach, so if you need to see a log or my tune PM me with your email addy and I'll send it over.
Thanks!!
Is the TPS setup properly? A TPS that is indicating a fixed value will cause shifting funki-ness like you described.
I had a transplant the other day in a little S-10 pickup that would do the shifting kick-down. Turned out the TPS was stuck at 100% after a TB "upgrade".
I had a transplant the other day in a little S-10 pickup that would do the shifting kick-down. Turned out the TPS was stuck at 100% after a TB "upgrade".
Thread Starter
Launching!
Joined: Jan 2009
Posts: 241
Likes: 0
From: Mead, WA
The APP sensors are used to determine the pedal angle. The engine control module (ECM) provides each APP sensor a 5-volt reference circuit and a low reference circuit. The APP sensors provide the ECM with signal voltage proportional to the pedal movement. The APP sensor 1 signal voltage at rest position is less than 1 volt and increases to above 4 volts as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near 0.5 volt and increases to more than 2 volts as the pedal is actuated.
APP 1 - .94-4.18v
APP 2 - .45-2.08v
Teching In
Joined: Apr 2011
Posts: 1
Likes: 0
TCM issue Did you ever fix this problem? I'm having the exact same problem w/ my swap and its the exact same eng. trans, ecm, tcm setup. Any light you could shed on this would be much appreciated. It does go away for awhile if I disconnect the battery but then comes back again w/o any codes? Please help if you can. Rob
Thread Starter
Launching!
Joined: Jan 2009
Posts: 241
Likes: 0
From: Mead, WA
Did you ever fix this problem? I'm having the exact same problem w/ my swap and its the exact same eng. trans, ecm, tcm setup. Any light you could shed on this would be much appreciated. It does go away for awhile if I disconnect the battery but then comes back again w/o any codes? Please help if you can. Rob
