...whilst booking the car in i was informed that the ecu needed new software and if the car had been chipped i needed to inform then as it could damage the ecu. does anybody know what the update does and if its nessersary, revo people says all will be fine and are going to charge me £40 to re install it.
....The VW update is probably 24K6 and is known to trash a remap though not intentionally.
I think this is all down to the way the new manufacturers map is applied. If the exisiting map is simply deleted, and a complete new one written to the EEPROM, then there should be no issues of corruption of the data, or damaging the ECU. However, if, on the other hand, the manufacturers software is merely an upgrade, then that is where the trouble will start. It would be like trying to update your AVG anti-virus with a database update from say Norton - it ain't gonna work!
If you have Revo then switch to Stock map before the dealer session and then go to your Revo agent afterwards before you switch back to the remap.
Yup, very sound advice Robin.
NOTE: Revo did NOT charge me for re-installation and neither did their agent, JKM Portsmouth. Something wrong if you've been told otherwise.
I personally wouldn't have a problem with paying for a re-installation, because you are afterall using their "commercial" time. I do think that £40 is a bit steep, though, and would consider around £20 to be a fair price. If, like Robin's agent, they didn't actually charge a fee at all, then I would bung them a tenner or so, to fill up the office biscuit barrel or coffee jars.