I've been having some problems with my 2003 s60 turbo starting up for the last 6 months. It takes a good 5-6 seconds to get it to fire up, like it is searching for fuel. If I turn the key forward then back, then forward again it fires right up no hesitation. Battery & alternater where replaced last year. Plugs & Coils I replaced this summer and it had no discernable improvement on the starting situation. What should I be zeroing in on?
Thanks!

 

Well, it takes fuel, air, and spark to start. My initial guess would be that your fuel pressure is low. Maybe your regulator or a check valve is bad.

Post some more info like, is this a cold start problem? How long does it have to sit for the problem to surface? Is it cranking every time?

 

It sure sounds like fuel related, need to get fuel gauge on this thing and see what your pressure readings are. Specs as follows.
Pressure (KOEO) 54-57 psi
Line Pressure@ Pressure regulator (55psi)
Residual pressure 29psi (minimum allowable pressure after engine shut down)
Hope this helps.