Problem with 3-4 shift

[tici]

When my A4 shifts from 3rd to 4th between 40 and 70 mph at part throttle it “looses” the gear for a moment (see the graph). The engine revs about 200 rpm higher during a very short time than goes down where it should. This takes less than half second but I can hear and feel it.
This happens only if the car accelerates just a little (15 – 20% TPS), with more torque it shifts just fine. The same happens if I shift manually.
The car has about 40’000 mi, the transmission fluid is fine (color, level), mods are just a FIPK and LT’s.
The stock shift time is 0.5 seconds; I’ve set it first at 0.7 then at 0.3 to see if it changes… still the same.
This problem happens no matter at which temperature.
It looks like it's a TCC issue... Do I have to replace oil and filter? Or just leave it like this?

Who could give me some idea to solve this problem? I always wanted to replace my A4 with a M6… but not exactly now!

Thanks - Stefano

[Casey]

TCC unlock during shift option??

Ken

[tici]

TCC apply during shift is set on FALSE, this is normal for F-body. I tried with TRUE, but it didn't change. I saw other posts about no difference between true and false... all using Edit (like me)
Does it work with HPtuners?

[Casey]

I was just going to say email me you binary and I will take a look. But I can't open an Edit file.


I assume you have read this?


If you have tried all of that and it still does not work, there is another bit option table for TCC lock. We will include it in a later update (might not make it into this one).


Ken

[tici]

This is a good starting point!
The stock 3rd gear TCC apply speeds has exactly the same numbers as the 3-4 shift.
This in the TPS range 12 - 31%.
My issue is also "apply in 3rd, unlock, shift to 4th, lock".
My solution (patch) was to eliminate TCC in 3rd. Not really a solution because in many situations you have to "help" shifting in 4th. Another problem is that the engine won't brake the car driving downhill (smoking brakes!)
I'll try to reduce the TCC apply speed a bit and post the result.

Thanks - Stefano

[Elmis]

Ken@HPTuners:there is another bit option table for TCC lock. We will include it in a later update (might not make it into this one).

Any overview of what the extra option table offers?

I'm finding my convertor has some consistent but odd behaviour that defies the tuned parameters.