is it worth doing every now and then, what does it actually reset and how is it done,and is it safe

This will remove the adaptive learning on the ecu, which intern will apply the original ecu map rather then one that has been "educated" to provide the most efficient drive and emission figures. I believe also it will force the TB to do a reset.

It is safe and can be done by disconnecting the battery for a few minutes ( say 5 should do it) or more simply by removing fuse number 10 for the same length of time.

cheers mate i might try that, will it then re learn and adapt to my driving style or does it just optimise itself

AFAIK you'd need to do a TBA after reconnecting the battery - this would require VAG-COM or similar. However if you have VAG-COM you can clear the fault codes on controller 01 and this will reset adaption values.

could i not just do the bonnet + door open with ign on TBA

I think that is a wives tale.

doh!!! looks like its a no go then as i don't have vag com

Its NO wives tale, it worked for me, ecu reset, cleaned up first then a TB reset, fitted a new battery, works every time no problem. Open the bonnet, open drivers door, give it 10 seconds or so and then you will hear the TB doing the business , it will be a high pitched noise as the motor moves the butterfly.

Try it, if its an old wives tale then you will have nothing to loose !! :)

i'll give it a whirl !!!

you dont need the door open n bonnet.

jus turn the ignition key on so le lights on the dash come on and leave it for 30secs - 1 min

you will hear a high pitched wine from the bonnet area, when it stopps and has been stopped for a while then it has alligned.

billy

when it stopps and has been stopped for a while then it has alligned.

If that were so then there would be no point in the official workshop manual specifying a procedure for adapting the throttle control valve to the engine control unit. This involves using diagnostic equipment and checking that the throttle control valve moves between specified values during the adaptation process.

JM2PW.

so what does it do then ? i tried it today, it did something it made the high piched noise for about 1 min