I had the weirdest running in with the current car (170TDI Roc). Straight off the forecourt it seemed so tight (compared to the previous car - 140TDI Roc) that if it wasn't for the soundaktor i'd have convinced myself that i'd been given a 140 by mistake. I drove it pretty gently, with the occasional incursion into 2/3 revs for the first 700 miles/1000km. I was pretty pissed off that my 170 seemed so tight, then at what seemed to be dot-on the miles equivalent of 500km (320 miles?) it was like someone had flicked a switch - the difference was instantaneous. Could my Roc's output have been retarded by the engine management during some basic running in program? I had never felt this in any of my previous 5 TDIs, but it did seem as if suddenly at 500km the engine management had decided to let me have access to more power.
When running in, get it on plenty of variety in speeds and revs for the first 700 miles. I bought 1 Golf 140TDI from a dealership in Crewe via a broker and then drove it straight down to Southampton. Running in on motorway miles stuck at 75mph ruined that car. It was thirsty, had less than average power and went through a litre of oil every 1000 miles, none of my other TDIs had ever gone through a meaningful quantity of oil between services.
If you have no intention of keeping it beyond the warranty then I suppose you could drive it like you stole it from day 1!
