MK 1 cab running poorly an rich when cold.

Hi all. I've an issue with cold start as when the car is first fired up from cold it runs like it's running on three cylinders, smells very rich but runs fine when it gets hot! Does anybody know if there is something I need to replace or a just on the injection system to stop this happening? I changed the spark plugs which made a difference but I've posted a picture of the ones I took out. Any advice I'd be really great ful. Thanks.

Could be leaking injectors, when the car is switched off petrol leaks into the cylinders.
Try unpluging your 5th injector (blue electrical connector) and see if that helps as that will stop any extra fuel being added on start up.

Worth  checking the  warm up regulater ( WUR ),   then the  thermal time switch..and …auxiliary air valve  . .