Well,
Car went in yesterday to have this problem looked at. I printed off this forum and handed it to the guy that picked up the car. "The garage called me back and said, we put it on the diagnostics and couldn't find anything wrong" What happened to good old fashioned mechanics and a bit of tinkering eh? I work in IT and I wouldn't rely on a PC to tell me what was wrong with it from start to finish! These self diagnostic things spit out more erronous crap than you could imagine! So how a car with all it's mechanics can get it right is beyond me!!!
So, The car had a couple of bolts on the boot door that had gone rusty (I have an 05 plate car) which they don't carry in stock. When the car goes in to have those bolts replaced, they are going to keep it overnight to see if they can simulate the problem.
I have to say though, apart from not taking the fault seriously, Webbers have been pretty good. They came and collected the car from me at work in Winchester, a good 20-25 minutes away from the garage at no extra cost to me. When I spoke to the guy in service at the end of the day and impressed upon him that I wasn't imagining this problem he didn't hesitate to arrange for it to come in for a couple of days. The car was dropped back to me before 5 in the eveining so that i could drive it home. Not bad.
I'll post again as soon as I have more news.
Meanwhile, Someone else said they had been to Webbers of Basingstoke. Did you ever manage to get the problem resolved with them?