I have a 2004 2.0 GT TDi Golf, I've owned it around two years and it has always had a bit of an issue starting quickly when the engine is very warm, more recently it developed a problem starting when the weather is very cold too. It was like the starter motor was sticking when cold and when warm it would just take longer to turn over before firing up. But it always started.
Very recently it stopped starting sometimes when either very cold or very warm. Unfortunately I have had an issue with the turbo and had many things changed while trying to rectify the problem, these included, glow plugs, injector seals, turbo, intercooler, starter motor (as I thought it was the starting issue) and a full flush and service.
It will start fine if bumped and I have noticed that when trying to start when cold it can lock the doors, turn on the alarm and turn on the A/C even if I have just turned it off before trying to start. I can also hear a relay clicking away. No faults are coming up but if I do try turning it over for long enough I get an oil pressure light come on and a workshop warning.
My mechanic is stumped and because it so intermittent its very hard to find the fault. Can someone help me, please!!