not sure mate, they were nkg v grove ones from halfords. I did try adjusting the gap but not properly yet as i don't have a feeler gauge. I read up in the manual it should be 1mm or 1.1mm. But im sure that that wouldnt cause this much missfire would it? Going to have another go at getting that last plug out tomorrow.

For some reason i think its the timing even though i didnt touch it!

Put leads on it. Fit that other new plug too.

Ill go for that first then as i was going to do it anyway. Its stoped doing it now.

If you can, would be worth wireing a voltmeter across the terminals so's you can keep an eye on the output...

No, not at all. If you use a multimeter, it has it's own internal battery and in any case it'll only read the voltage when the alternator is turning. The current draw is minimal anyways, so no worries.

Connect the + lead to the alternator and the - to your battery negative. You should see around (certainly no lower than) 13.8Vdc whilst driving around. If the multimeter leads are too short, they can be safely extended with speaker wire, just make sure the connections are good.