Car pulling back cutting out and refusing to start

[vrs lil]

I bought a MK3 8 valve a month or so ago. It was running lumpy so tried the obvious and changed the lugs and leads and it ran perfectly. It does seem to pull back a bit on gear change so am thinking this may be the dizzy cap and rotor arm of which I've yet to change.
Yesterday I done a longer journey and went to pull away and it started running lumpy and I had to rev it to make it run ok.
Last night when driving home late it lost all power and stalled. It then refused to start so had to leave it and walk home.
Just gone to get it and it started fine and drove home ok though a bit hesitant.
Sure it will happen again but have no idea where to start.
I'm gathering it's a common theme here so any help appreciated.
When it's running it runs fine, no smoke, excess fumes though does smell a bit eggy/ carbon like or could just be me looking for fault.
Thanks a lot
Paul

[vrs lil]

I've had a look and the oil breather pipe going from the block had a huge split in it. For now I've cut it and placed it back and it seems a bit better. Is this one cause of the issue?

[Gti_Jamo]

Could well be, also your mass air flow meter on your air box can cause this too. Try disconnecting it and see if it drives any better. If it does, its knackered or needing a good clean out.

[andy-gti84]

check all ya wires as some do come lose etc main earth wire as well an check ya lambda sensor as can course ya prob like this. 

[vrs lil]

I'm off to work in a bit. I'll see how it drives now I've kind of sorted the breather pipe. If it plays up I'll try the air flow meter unplug and go from there.
Many thanks guys

[AcidicDavey]

My car had exactly the same symptoms you report when I got mine, turned out to be a faulty coil.

Try and get your hands on a working one and swap and see if that helps.

[vrs lil]

Got all the way to work and then it cut out and refused to start. Left it ten minutes and it started fine. So the issue is still there annoyingly

[Screech16v]

Id say either coil or crank sensor .

[kylepeo]

i would go with coil got me a new 1 from andrew pages for 48 quid was a febi item too and sorted all my problems

if not this then look at crank sensor
also worth a look at ecu relay and fuel pump relay
(original where made in tunisia and where a known issue easy to check just drive for around 15min relay should be warm cold relay means dead relay)

[vrs lil]

Left work last night it started got to the top of the drive and the revs dropped. Managed to keep it going then when I changed gear it spluttered to a halt and refused to start.
Left it for the night and today it won't start at all and the oil light is flashing as I turn the key.
I saw on here that the number 30 relay causes issues like this.
I'm not sure what to begin with.
Does it need VAG com to diagnose or hold I just start by buying a relay?