I have a 1.4 automatic Lupo, 2000 which has trouble starting in hot weather. On cooler days I have no problems, but on hot days, particularly when my car is in direct sunlight it struggles to start. It just cranks and cranks but struggles to fire. Sometimes it takes 10 tries before it starts, other times only a couple. Weirdly this rarely happens when I start the car for the first time in the day, only when it has been driven around and the engine has been switched off (so I'll park up, pop in the shop, come back and it struggles to start). Luckily it has always started eventually, but I know it's just going to get worse. Any ideas what it might be? After reading on here about it possibly needing a new crank sensor, I took my car to a mechanic who said if it was the crank sensor I wouldn't only have this problem in hot weather? I also ruled out it being a problem with the immobiliser as I have the same problem with my spare key. I'm thinking about buying a diagnostics tool myself to find out what the problem is rather than taking it to the garage to diagnose. I have read on this forum about vagcom? But have no idea where to start!