Is it the TDC / Crank or Spark Plugs?

[Mr Me]

Hi Guys, Happy New Year, a quick question hopefully...

the clio takes a second more time to start now, seems like it doesn't want to start then its fine. I've had a good look on here and it sounds like the TDC / Crank... which sounds like a pig to fit as it needs soldering? anyway, could a dodgy plug cause this kind of problem as they are due to be changed soon?

Thanks!