You might check fuel system pressure and see if it holds between runnings, or if it bleeds down to zero pretty soon after you shut off the engine.
If it doesn't seem to hold pressure well, you might re-check the FPR and connections at the fuel filter. I don't know if the 3.3 uses the same FPR as a 3.5, but if it does you might have an o-ring issue.
Short version: On the 3.5, the FPR uses an upper and lower o-ring. Sometimes the lower one doesn't come out of the cavity in the fuel rail, or sometimes fragments of it are left behind. More often, an incorrect install procedure leaves just enough of a pressure leak to cause starting problems but not enough to show leaking fuel. Correct procedure is to oil o-rings, install lower one into rail cavity *first*, install upper on FPR, then 'snap' the FPR into the cavity.
That doesn't intuitively look like the right procedure, but it for sure is. Don't know if it applies to the 3.3, though, but even if it doesn't you might look around for a spot where system pressure could be bleeding off between runs. The approx. 1-second fuel pump run at key-on usually isn't enough to pressurize the whole system unless there was already residual pressure. If not, (at least on the 3.5) it can take as many as 4 or 5 key-on cycles without cranking to get full system pressure. According to my experiences and my fuel pressure gauge, anyway.