4L80E shifting too early
#1
4L80E shifting too early
Just swapped a 4l80e into a 2000 t56 camaro, segment swapped using HPtuners. I'm getting intermittent part-throttle early shifting. When it happens it will shift both 1-2 and 2-3 and lock the converter at the 0% TPS column of the shift/tcc table. Any ideas would be welcome, I changed the TPS even though it never actually dipped in the logs - no help. Tune/log/config and screenshots attached, only code is P0103 (speed density).
Good shift
Bad Shift
Shift table
Good shift
Bad Shift
Shift table
#2
Still cant figure it out. Changed the 0% TPS column of the shift table a few times and the intermitent early shifting follows. Attaching another log/config/tune with more pids logged along with status bits.
Good shift:
Bad Shift:
shift table:
Good shift:
Bad Shift:
shift table:
#3
Bumping this one back up. The bad shifts seem to correlate to a higher TCC slip. All the good shifts are at a lower TCC slip (3-500) and the early shifts are at a 600+ TCC slip. I've been playing with the P1870 stuff as a result with no success but its never set a code.
I attached the current tune, log and layout file (3.0 hptuners).
Good Shift:
Bad Shift:
I attached the current tune, log and layout file (3.0 hptuners).
Good Shift:
Bad Shift:
#4
huh looks like you got the PWM turned off which is what I was gonna say. did you max the pwm pressure tables or just disable the code?
what does it do in D3? same short shift 2-3?
what does it do in D3? same short shift 2-3?
#5
Are you talking about the TCC PWM%? It locks in both those screen shots (100%) after shifting to 3rd.
All this is in D3, I believe it does it in D4 too but I'd have to check some old logs as I usually drive in D3. It short shifts 2-3 also at the 0% 2-3 value of the shift table sometimes. It also locks the converter at the 0% TPS value of the TCC table sometimes.
All this is in D3, I believe it does it in D4 too but I'd have to check some old logs as I usually drive in D3. It short shifts 2-3 also at the 0% 2-3 value of the shift table sometimes. It also locks the converter at the 0% TPS value of the TCC table sometimes.
#7
That would be great. I'd even eat the credits at this point and flash a known good file for lack of any other ideas. I'll pm you my email in case you dont want to post it.
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#8
ok i sent it email just to be sure but here it is again.
If you want to start fresh I can look in my computer for a 4l80e segment that matches your OS # that way to you dont spend any credits.
oh and I was gonna ask how you pinned out the trans connector and if you were using a range switch.
I just went through this swap myself and it took some fooling around to really get it dialed in.
If you want to start fresh I can look in my computer for a 4l80e segment that matches your OS # that way to you dont spend any credits.
oh and I was gonna ask how you pinned out the trans connector and if you were using a range switch.
I just went through this swap myself and it took some fooling around to really get it dialed in.
#10
Ok then, the trans segment from my truck ought to work. Make sure to also grab the trans diagnostic segment too.
Oh and select "none" from the drop down for the range switch, mine is tuned & wired for P/N only.
Oh and select "none" from the drop down for the range switch, mine is tuned & wired for P/N only.
#12
#13
I've been thinking about this for a while, I dont know why I was so stingy about HPT credits. The swap file was 2002 Silverado with a 6.0l / 4l80e. Grabbed it from the HPT tune repository.