Auto box playing up

[entwistlea]

Hi All

 

Hoping an Audi Auto genius out there may be able to help.

 

We have recently bought a 2004 A6 Allroad with auto. When we picked it up we felt it was hanging onto the gears a little long and changing late, so we have changed the fluid and the filter.

 

Since then a new and interesting issue has arisen and we're trying to understand if the box is shot, if its ECU or something else.

 

When changing up, it seems to carry out a semi change or phantom change. For example, If the engine is at 2000 rpm and it changes up, the revs drop briefly to say 1800 and hold as if in the next gear for a second maybe, before dropping again to 1600 or so as it takes up the next gear (obv this RPM varies depending on driving, but the symptom is the same).

 

At first i thought it was changing up twice in succession, but having monitored the gear changes it isn't.  It seems to be fluttering between gears before changing up, its a very strange issue.

 

has anyone heard of this before? I could understand if it dropped down in revs below as if in a neutral and then back up, but this seems to be changing to a rev band between gears before taking up with noticeable take-up of drive. No thuding of gears.

 

When we carried out the oil box fluid change i checked, no swarf in the box or on the magnets and all seems to be clean in the box.

 

We've bought this car as part of a charity feature we're writing ( we publish a trade mag) and are planning to sell it to raise money for GOSH ( think of it as a Trading up type thing) , so obviously we don't want to spend fortunes, especially on random solutions, so if we can find a solution it will help us to decide what to do next 

 

Any help would be much appreciated