Wont start when cold?

What plugs should be in a 95 jap spec wrx?

My car has developed a problem recently. It wont start when cold. Well it will after about 20seconds of turning over. And then it sounds like it is misfiring when it is running. Now once i start driving it then it seems to be ok. And its not down on power or anything. And if i try and start it once it is warm then it will start.
Anybody know what this could be? Could it be that the wrong spark plugs are in the car?

Thanks

could b the wrong plugs.did u have them changed recently?????

temp sensor!!!! :dunno:

Yeah, i'd bet on the engine temp sensor, it effected my car in the opposite way, started from cold no problem but found it hard to re-start once warm.
Subaru in Crumlin replaced it in a day and gave mine a tune up.