Missing on one, then two, then wont start.

[roar]

Come out of tesco and get in the car, start her up and its missing on one cylinder. As I am coming trhough town it drops out another cylinder. I just about manage to limp home on two and park. Then after a cup of tea come back to it and it wont start.

Its a J reg Mk2 8v GTI.
Any ideas?

[oakgreener]

Dizzy cap. Rotor arm for starters.

[raferackstraw]

+1 i would say with the amount of rain we've had water has got in somewhere

[roar]

Done the dizzy cap. Still not starting.....any further advice?

[SoundillusioN]

Done the dizzy cap. Still not starting.....any further advice?

No point chucking money at it buying things that may not need replacing. Properly check for a spark at each plug, at the same time this will help confirm that the coil is OK..  If all four sparks work, then you you know it's not the ignition system, if they don't then we can go into what the cause is.

[Diamond Hell]

If you're taking the plugs out - compression test as you go.