Vag-Com Log of Trans Hunting! Flog this horse!
01-09-2007, 04:16 PM
#21
Re: Answers
At least the half shaft stubs are required for front wheel bearing function. Weight on the wheels without the axels in makes for flat spots in the wheel bearings.
CalG
CalG
01-09-2007, 06:24 PM
#23
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Video of my tranny hunting on youtube....
Ive posted my video of my tranny hunting on the way to work last week. Is this what everyone else is seeing? Pay attention to 1:24 when I start to accend on a bridge.<ul><li><a href="http://www.youtube.com/watch?v=Uxb7HmXbTHE">http://www.youtube.com/watch?v=Uxb7HmXbTHE</a</li></ul>
01-09-2007, 07:38 PM
#26
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suggestion...
if you can re-create a simple scenaio where the hunting happens, then we will get others with vag-com to replicate with their hp24a's, and compare results.
e.g. attain 50km/hr, in "d" (5th), downhill in overrun. hit "marker" then monitor for 10 secs.
then should be relatively easy to compare results...
paul's experience interests me. there is a possibility that the motronic is involved in instructing the tcm to slip, or that the tcm is instructing the ecm to retard. again using the above approach we could repeat the same test with the ecm to ascertain what it is doing...
any takers?
e.g. attain 50km/hr, in "d" (5th), downhill in overrun. hit "marker" then monitor for 10 secs.
then should be relatively easy to compare results...
paul's experience interests me. there is a possibility that the motronic is involved in instructing the tcm to slip, or that the tcm is instructing the ecm to retard. again using the above approach we could repeat the same test with the ecm to ascertain what it is doing...
any takers?
01-09-2007, 08:14 PM
#27
Yes, group 7 by itself (for faster sampling) would be interesting for trying to see ...
(1) whether the hunting transmission has larger converter slip rpm changes in response to similar N218 current changes,
(2) whether the hunting transmission has delayed converter slip rpm changes in response to similar N218 current changes, or
(3) none of the above.
Other tests can be imagined. Remember that logging more groups reduces the sampling rate.
The non hunting cars should be pre-2000. I've seen the newer TCM software work around what would otherwise have been a thump.
Those who have a hunting car and think the ECM has some role might start by logging the ECM values as seen by the TCM during hunting. (I don't personally think they'll find much, based on how a fresher, new-design valve body eliminated Tozo's hunting.)
Tom
(2) whether the hunting transmission has delayed converter slip rpm changes in response to similar N218 current changes, or
(3) none of the above.
Other tests can be imagined. Remember that logging more groups reduces the sampling rate.
The non hunting cars should be pre-2000. I've seen the newer TCM software work around what would otherwise have been a thump.
Those who have a hunting car and think the ECM has some role might start by logging the ECM values as seen by the TCM during hunting. (I don't personally think they'll find much, based on how a fresher, new-design valve body eliminated Tozo's hunting.)
Tom
01-09-2007, 08:23 PM
#28
When you saw increasing slip with increasing N218 current, was that at constant throttle?
If so, the TCM is definitely not getting what wants from the hydraulics or clutch!
(Your valve body diagram shows two ways they tried to make clutch apply pressure correspond predictably to N218 current -- the D-V2 pressure regulator for control pressure supply, and the WK-V output pressure feedback on the opposite end of the spool valve from the control pressure.)
Tom
(Your valve body diagram shows two ways they tried to make clutch apply pressure correspond predictably to N218 current -- the D-V2 pressure regulator for control pressure supply, and the WK-V output pressure feedback on the opposite end of the spool valve from the control pressure.)
Tom
01-09-2007, 08:26 PM
#29
Was the 320 rpm slip with 0.488 A on light throttle?
That seems to be more slip than they ever want during the regulating phase with light throttle, but that's based on logs with a 2001 car which in some ways has different TCM software.
Tom
Tom