Mk3 Golf Intermittent Engine starting problem

[bristolmilo]

Hi guys new to the forum.
I'm hoping that someone can help solve my engine starter problem. Whats happening is every now and then i turn the key and it trys to start but just keeps turning. It started when i bought it and i changed the the plugs, leads, dizzy cap and arm to rule them out. It was fine for a few months but now has started again. I called the rac out and the guy said its either something in the main wiring loom or ECU, but ive been told since that because its so intermittent it cant be the ECU. I also changed the No36 relay, as i was told that was the something to do with the ECU but i still have the problem.
Now im no mechanic but from watching the RAC guy it did look like some sort of spark delivery problem, not on the plugs but on one of the other connectors (cant rermber which tho). The coil pack works as a guy i know put a votage tester on it.
Sorry if this seems a bit all over the place but im just talking from memory. If anyone can help i'd be most greatful, as i don't fancy being stranded again.

[tshirt2k]

Have you checked the coil? I had this problem. Coil insulation fails and let's moisture in in cold damp mornings. Once heat from engine dries it out, it starts ok. Check coil resistance if you can. Or check colour of spark. It should be blue not orangey yellow.

[bristolmilo]

ive been told the coil is fine. The weather doesn't seem to affect the problem anyway as it happened the other day when it was blazing sunshine

[bristolmilo]

 It's a mk3 golf 96 2.0 8v by the way

[tshirt2k]

Coil can still be breaking down. Unless you measure resistances you wont know. Doesn't mateer what engine. They all use same coils