My S2 has developed an issue when starting from cold

It takes around 6-8 seconds to fire, just cranks for a while before firing. And then it runs like crap

Ive noticed if i let it start with no throttle, when idling rough, Volt gauge is reading 10-11V... as soon as the engine settles it jumps to 13V

The car has had a service 2 weeks ago, new dizzy cap, rotor arm, spark plugs, HT Leads, Oil and Fuel Filter

I suppose it'll be better for me to go EFi as soon as i can