Mk3 Misfire.

[Bambam]

G'day folks.

I have a '98 8v Gti with 114,000 miles. It's nothing special, a bit scabby in places but it does the job just fine.

A few weeks ago I noticed a slight misfire and so serviced it with new plugs, filters and fluids. I couldn't get the correct HT leads so left that for later (it's a late Mk3 and I often find the 'correct' parts are not that at all). After servicing the misfire seemed to be worse so I tracked down the leads and fitted them. No joy, in fact the problem is more obvious, so I'm wondering where to go next?

I'm okay with swopping parts myself and simple diagnosis but without knowing what to change I'm stuck. Injector? Fuel pump? Something on the ignition circuit?

[Rmachines]

Coil pack causing a weak spark,  it will suddenly give up on you so make it your next item to check. 

Very common,  I keep on in my glove box now 

[Bambam]

I was about to swop that but read a reply to a post I'd made on Pistonheads (same question). Someone said it sounded like the fuel pump relay which was known to cause the symptoms I described before leading to the engine cutting out as it stopped the fuel pump at random.

Guess what happened last night?

Without warning, 40mph, the engine died. Coasted to the verge, turned the key, engine started, drove off.