Definitely electrical as you say.

I'd start by changing the OVP for another one.

It sounds like the warm up cycle - second (?) stage of the starting routine is being missed or messed about with. If you look in the FSM there's a description of this routine (in flow diagram form if I remember correctly) - it relies on the water temperature sensor => is also something I think you need to check.

Water temp check is easy - see book - measure resistance - compare with ambient temp / water temp

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!