Have developed a plan to try and resolve this. One possible cause is a leaking fuel pump check valve. Is this valve part of the pump? If not where is it? If it is in the pump can it be replaced alone or have to replace the whole pump? From my Haynes manual it appears I have to drop the tank to get at it.
Background
I'm thinking there are three possible causes of this non-starting (but runs fine after it starts) issue:
1. Fuel Pump Check Valve leaks $$- This explains the loss of fuel pressure in the rail when shutting down engine. From my Haynes manual it says the pump only runs 2 seconds when the key is first turned on. If the pressure that develops after 2 seconds is not enough to start the engine, the pump never runs again so there is no fuel. If it starts then the check valve is not really needed until the next start.
2. Fuel pressure regulator failed or leaks $ - Similar to the check valve the regulator may be passing too much fuel back to the tank resulting in a low pressure. After the engine starts the ECM goes into closed loop control and may compensate for this low pressure. This may also explain the cold start issue as I expect more fuel is required for a cold start. Further when I replaced the camshaft sensor a few weeks ago, I found the vacuum hose to this regulator disconnected. I have read that the fuel pressure should go up about 10 psi when you disconnect that hose. So when I "fixed" the hose connection I may have made the problem worse. Could explain why the problem got worse so quickly in the past few weeks.
3. Fuel Injectors Leaking $$$ - This also would explain the loss of fuel pressure. However, one would think this would cause some running issues also. Further one would expect this may may the engine easier to start when cold - unless there is way too much fuel and I'm trying to start in the flooded condition.
I'm hoping for #2 due to cost. I think I can narrow it down to 1 & 2 by turing the key on an off several times leaving it on for about 3 seconds each time, and then trying the start. From there hopefully determine if it is the check valve or regulator by pinching off the supply and return lines respectively. Looks like it will cost me a fuel pressure gauge in any case.
Ron