oooo ooo ooo oo i have another idea, i had this on mine after fiddling with the battery, there is a relay down in the inner wing between the battery and the inner wing, i think it was green (dont hold me to that) but it had corroded terminals, i had to replace the relay and rewire the terminals, deffo worth a look, that was similar to your prob, the car was running fine, i moved the battery to check something else, re seated the bat ready to go home, and all it did was constantly turn over, fixed this relay, and been fine ever since.
check it out, and let me know. i feel good when i have helped someone
p.s there are a lot of relays there, check them all to be on the safe side, or do what i did and move them about while turning over, it may fire and you will know.