From cold the car starts fine, drives fine, all is normal as far as I can tell, but If I get the car warmed up and then stop it for a short while, to go into a shop for example, then often when I come back to the car it will badly misfire and will not clear with revs, I have to turn it off and on again, often multiple times, until it starts normally, at which point all is fine and it drives fine, It is progressively getting worse.
A bit of throttle when it's misfiring and it stinks of fuel with associated vapour from exhaust so it kind of seems like it's creating a flooding condition but I don't understand why?
I suspected perhaps ECU coolant sensor but it seems to be reporting fine to Nistune unless intermittent. Put new plugs in today as was doing oil and fiter anyway. I have a new dizzy cap, rotor arm and coil there but not sure if it's ignition component related. cold idle valve always open perhaps? There are no fault codes.
Any ideas or anyone experienced this?