Always Overcharged

can be viewed clearly and the thump seems to be a shorter occurence of the same condition.
results are still unconfirmed so reluctant to call definitivley yet.Logs required to confirm and further study are as follows.

From a non hunting car-Trans 001-003-007 logged together at cruise

From a hunting car -all trans groups logged one by one with groups 001 and 007 included in the same file.[similar driving at cruise please to show hunt if possible]
Sorry I know its a drag but I have a good feeling that there may be some answers here.

If anyone would like a copy of the notes showing progression of this study please email me.[A copy will be sent to all contributers of logs as a matter of course]
This is by no means a complete document and all considered input welcomed.
Thanks again for the log contributers so far.

ttuling

... in case there are subtle changes in converter clutch control among the later cars which don't hunt.

I don't know if the logged data points are frequent or simultaneous (across fields) enough to let you prove whether the TCM commanded excessive lock/unlock or merely reacted to it, i.e. whether the thing that changes to enable hunting is outside or inside the transmission. I'd bet on "inside", for reasons described elsewhere.

Tom

Always Overcharged

yes please

CalG

Reviewing logged data does not give clarity to the event sequencing, as you have mentioned Tom.
I have inqired about the VAG-Com Data on that forum, but have not received a useful response

Something that is evident however, is that the N218 solenoid current value always moves to the same initial value when directed to Regulated mode. And then is restrained to small changes unless commanded to fully open or fully locked.

This value ( near .45 amps) sometimes does not provide the correct slip rate, and then the control system plays catch up until another big jump in current demands a lock up.

Quantum control current changes that are not perfectly suited to the requirements for slip management. Why can there not be a broader range of control values between unlocked and lock up?

I have seen somewhat higher values (towards lock up) during deceleration events. There must be more range available.

It may be true that if the response to close the TCC was more rapid, the engine RPM/ Transmission slip speed could be held in check. Doesn't the combination of acceleration request and engine load trigger the TCC slip command in anticipation of a down shift? Logs display the N218 command in sync with Engine load displays. That was the thinking behind the TPS exchange.

It is quite an interesting system, the entire Torque Converter runs in pressurized oil prevent cavitation with controlled oil flow-through to perform heat exchange functions.
A diaphram spring applies a force to the friction surface of the TCC to effect locking. When the correct valves redirect the oil flow, with more oil allowed into one side of the TCC, the spring pressure is releived, and cooling oil passes over the friction surfaces. And these surfaces can generate considerable heat when acting as a speed compensating friction drive.

Literature suggests that the sophisticated control of of such systems is not practical without fast computation electronics and software.

Regards

CalG