I've discovered after further investigation to my smoke problems that number one plug is wet,it does'nt really smell of fuel but was definately wet.when the engine is started from cold it runs on 3 cylinders for about thirty seconds then runs fine but smokes quite heavily,it does'nt smell like oil burning.Does this point to a leaky injector?if so are they servicable or is it as well to replace the leaky one or all four.should the fuel pressure regulator also be inspected and replaced at the same time or am i barking up the wrong tree altogether.