hello newbie with a few questions.

[andy draper]

Hello,all my names andy.I have just purchased a 2001 2.0 ts with 136000 on the clock and would really appreciate some advice.
What does all the T4 T5 etc mean please and what is mine?
I have a problem with the car from cold,for the first few miles,or untill it is warmed up on my drive,the engine misses and runs really rough,when it is running at temp it is smooth as anything.Before i start ordering parts i wanted to see if anyone had any ideas as to what could be causing it.The car has a full service history from volvo initially then from an independant,and had a service before i got it.I have checked the two ignition leads and one looked very clean around the insulation cover,and the other was looking a bit burnt so i am ordering new ones,after i manage to work out which ones are compatible,so i'm hoping it could be one of these.The coil packs look very clean,not that that's anything to go off.There are some wires coming off a unit under the top left of the cover and the armoured plastic has gone brittle and come off exposing the coated wire but no chaffing or bare wire is showing.
Which are the best plugs for this model,and where can you get one of those air splitters from please,there is a new middle piece it's the n/s bit that's broken off,or is it best to just remove the lot.
Sorry to introduce myself with so many questions,hopefully this will sort the car out.
thank you in anticipitation,
andy draper.