1999 1.8 MX-5, has developed a misfire when starting from warm only. Go to get petrol, nip into the papershop, etc, come out restart and MISFIRE. It sometimes cures itself, but yesterday it was there for 20 mile journey, (no very worried about destroying the cat and bigger bill !). If we leave the car for and hour or so & come back & restart it then often the misfire has gone.
So far, used different petrol stations, filled her with optimax and replaced HT leads.
Any ideas please ?
There does seem to be millions of threads on similar but anyone help please ?
The second thing is has anyone got a diagnostics machine in the Colchester / Ipswich area that could plug it in to find the problem in exchange for some cans of beer or a bottle of wine please ?
Most likely cause is your coil pack is on the way out. Is it misfiring on 1 or 2 cylinders, if it’s 2 then I’d definitely favour the coil pack. I had the exact same problem on my mk2 - only misfiring when restarting from warm. Changed the coil pack and it’s been fine since.
Yes it is possible to replace them individually. The problem is finding one[:)] It just so happens I have one in my garage but unfortunately its for a MK2. Try ebay or put a wanted ad on this forum - depends how quick you want one though. MX5 parts are a lot cheaper than your local Mazda dealer and are also genuine Mazda parts.