i had the usual 4500rpm > misfire and it really pissed me off. i tried taping them up, it worked for a little while then after a few hours it buckled on me again. i tried araldite and i waited around 12hrs for it to dry, put them back in and after 2 weeks the problem came back.
i figured there must be a reason for why the spark wants to travel through the hairline cracks rather than through the coil..
looking at the coils, i noticed that the copper part was looking a little crappy. it looks like it had a build up of carbon (or something else) on the inside so it occured to me that the spark may have been finding another route to earth as the normal route was no longer the easiest/shortest (electricity travels the shortest path possible).
this is what a bad one looks like:
as you can see here, it looks like complete crap.
i didnt know that this was what it was meant to look like, i thought it was normal till i tried this fix.
this is how to REALLY fix your coil packs:
you will need:
- a dremil drill with a small sanding attachment.
- WD40, vaseline or de-oxification paste
- the usual tools to remove your coils
1. first took apart your coils (rubber boot and spring off)
2. get a dremil drill set out and lightly sand back a very thin layer on the inside of where the little spring sits inside the coil.
(around a teaspoon of build-up came off the inside of my coils. this was the gunk that was stopping the current getting to the spring, to transfer to the spark plug).
3. clean the coil out, preferably with a blower, but you could just tap it and it will mostly be out anyway.
4. spray some WD40 into the coil pack to stop it from coroding. i've just found out that vasoline or electrical de-oxification paste would be better for corrosion proofing as theyre conductive. WD40 isnt. i used WD40 and had no problems but if i ever take my spark plugs out again i'll be sure to give it a go.
this is what they should look like after:
Done.
i did this fix over a year ago and i havent gotten a single misfire since, im not using any bit of tape or araldite.
i've never tried putting splitfires in my car, but id imagine it'd feel pretty much the same. big call? try it for yourself.