Excessive Converter Slip?
05-04-2013, 06:54 PM
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Excessive Converter Slip? I've dumbed down misfire detection and that took care of my converter unlocking and then staying unlocked but it didn't take care of what I thought was the converter coming unlocked at highway speed.
You can see in my log at 17:44 that converter achieved a slip RPM of 1690 while in the locked mode! That's ridiculous! Any ideas what could cause this? Could it be electrical or something is busted in the converter? If you look later at 19:58 it's acting normal again, so I know it can lock up when it is acting right.
Also if it is relevant, the car still won't shift at WOT. It just pegs the rev limiter and hangs until I let out.
You can see in my log at 17:44 that converter achieved a slip RPM of 1690 while in the locked mode! That's ridiculous! Any ideas what could cause this? Could it be electrical or something is busted in the converter? If you look later at 19:58 it's acting normal again, so I know it can lock up when it is acting right.
Also if it is relevant, the car still won't shift at WOT. It just pegs the rev limiter and hangs until I let out.
Last edited by xXSilencerXx; 05-04-2013 at 08:07 PM.
05-04-2013, 07:46 PM
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Look at your commanded line pressure at cruise; I've seen
0%, even up grades, and my old TCI would flare, set P1870
and then refuse to lock until next key-on.
Back then I didn't have any way to fix it other than the
force motor table, so I shaved that down to increase
the actual line pressure delivered, for 0% commanded.
Now some models/years have the Transmission General
Pressure stuff accessible in HPTuners, which lets you
set a bump-up based on TCC locked.
The WOT-not-shifting, I dunno. I'd look at the current
gear PID and see whether this is an intention or an
execution problem. If it says it shifted and nothing
happens, that's not good. But maybe there's just
some "can't get there from here" in your part throttle
or WOT shift tables.
0%, even up grades, and my old TCI would flare, set P1870
and then refuse to lock until next key-on.
Back then I didn't have any way to fix it other than the
force motor table, so I shaved that down to increase
the actual line pressure delivered, for 0% commanded.
Now some models/years have the Transmission General
Pressure stuff accessible in HPTuners, which lets you
set a bump-up based on TCC locked.
The WOT-not-shifting, I dunno. I'd look at the current
gear PID and see whether this is an intention or an
execution problem. If it says it shifted and nothing
happens, that's not good. But maybe there's just
some "can't get there from here" in your part throttle
or WOT shift tables.
05-04-2013, 08:01 PM
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Look at your commanded line pressure at cruise; I've seen
0%, even up grades, and my old TCI would flare, set P1870
and then refuse to lock until next key-on.
Back then I didn't have any way to fix it other than the
force motor table, so I shaved that down to increase
the actual line pressure delivered, for 0% commanded.
Now some models/years have the Transmission General
Pressure stuff accessible in HPTuners, which lets you
set a bump-up based on TCC locked.
The WOT-not-shifting, I dunno. I'd look at the current
gear PID and see whether this is an intention or an
execution problem. If it says it shifted and nothing
happens, that's not good. But maybe there's just
some "can't get there from here" in your part throttle
or WOT shift tables.
0%, even up grades, and my old TCI would flare, set P1870
and then refuse to lock until next key-on.
Back then I didn't have any way to fix it other than the
force motor table, so I shaved that down to increase
the actual line pressure delivered, for 0% commanded.
Now some models/years have the Transmission General
Pressure stuff accessible in HPTuners, which lets you
set a bump-up based on TCC locked.
The WOT-not-shifting, I dunno. I'd look at the current
gear PID and see whether this is an intention or an
execution problem. If it says it shifted and nothing
happens, that's not good. But maybe there's just
some "can't get there from here" in your part throttle
or WOT shift tables.
Thanks for the insight! I'm still learning on the little tricks I can use this to maximize the usefulness of this software.
I was getting the same problem with it setting that code and then having to turn off and turn back on to get it to lock again. After reducing the sensitivity of the misfire detection, it didn't fail to "lock" once today in the sense that I could feel it or I saw the status bit indicating that it was locked.
For the failed shifts, I'm afraid it'll end up being mechanical but it's worth trying to troubleshoot, since that doesn't cost me money like doing a full rebuild will. I'll try dialing in the PID next time I take it out and watch it to look for that condition.
So looking through I don't see any general pressure stuff for the TCC menu, just apply/release speeds, shift lock, TCC Duty Cycle, and Minimum Throttle Release. Under shift properties there is shift pressures, and max pressures and I see Force Motor Current. Are you saying that reducing the current values in that table increase the pressure?