Vcds is a diagnostic tool specifically for VAG group vehicls, and is produced by a company called Ross-Tech.
It is an aftermarket diagnostic tool that can be used to read fault codes on all modern vw cars and vans.
It can also be used to re-configure certain features of the vehicles, such as max speed, enable fog lights, multi function steering wheel etc etc,.
Late vehicles (2010 -on) need the more expensive CAN based version of VCDS, whereas earlier ones get away with the cheaper version.
Where are you based? If you are in the Stroud area, I would be happy to have a crack at clearing this for you.
I live near Salisbury an looking on a map your prob about an hour an a half away. I can do it at any weekend except Bus types weekend as I'm off there. I have a good sat-nav so just your house number an post code an I'd have no trouble finding you. Ivan
VCDS can be used to REDUCE the speed limiter, but it absoutely cannot increace it again. Its a one way trip written into the ECU software, to stop people meddling with fleet vehicles that have been restricted as company policy.
You need a remapper / tuner to rewrite the EEPROM - Exactly as 155mph restricted sports cars are derestricted.
Thanks for all your replies guys. The tuning website looked a good idea to get it sorted. I'm not sure if a vw dealership could do it, to be honest i didn't about thats cos my initial question was can i do this myself. but reading your messages, clearly i cant!! LoL
Ah! just seen the rest of your comments captain, yes, been there before with my old T25 which had the chip in the ECU corrode out, along with the tow back to the garage, it cost me all in 700 quid to fix an get back!!!!!!!!!!!!