Cold starting strangeness

[Digbum]

Hi all,

I'm new to Passats after swapping my 1.9td Mk1 Caddy for a 2001 tdi wagon a couple of weeks ago. So far im loving it, even after the fun of tracing a leak in one of the turbo hoses causing me to drop into limp mode. Managed to fix that all by myself.

Now iv developed a strange cold starting problem. I was hoping you guys might be able to point me in the right direction as I'm wondering If it's an immobiliser issue, and I'm not used to such new fangled tech.

The problem is - When left overnight the passat won't start properly. After the initial start each day, it starts every time on the button.

What happens - on cold start I put in the key and wait for the plugs to heat, then turn over. The car starts immediately, but cuts out again maybe a second or two later. On the next turn of the key it will refuse to fire up for 15 or 20 seconds, usually kicking into life once a warning of low oil pressure flashes up.

My amateur opinion - It feels like the initial cut out is caused by no fuel getting into the engine, even though i can hear the pump priming when i stick the key in the ignition. This makes me wonder about a poss key/ immobaliser issue? I only have the one key and it's pretty battered. Is this a likely cause? How can I check it out?

Failing this I guess I'm looking for leaks in the fuel system or maybe a faulty pump?

Also - My battery light stays lit until the engine is running. I'm off to get a multimeter this afternoon to see if iv just drained my battery by over cranking the starter every morning. Praying my alternator is ok. Could a slightly bad battery be linked to the starting issue? Think my glow plugs are fine and it's not exactly been cold recently...

Any advice on what to check out next?

D