spider won't start

[Nancy Barnes <naneb@domain.elided>]

Ok. I thought we had solved my spider's problem but, it still won't start.
I left to go to the store and told my "mechanic" son to see if he could
figure out what was wrong. I  came home to no son but I note which read. I
fixed it. I tryed the car and it started right up. Hallelujah!! Well, I
went to the mall and when I came out it would not start. I had to get towed
home. The starter turns, there is spark, new battery with plenty of juice.
The fuel pumps, coil, distributor and valves are all new. This car wants to
start, but it just can't quite manage it. We thought it might have a vapor
lock. Before my son tried to start it I had pulled the fuel hose off the
fuel rail to make sure that there was gas at that end. I did not try to
start it again. When he tried it started right up. Any ideas? How do we
detect air in the fuel line or a vapor lock? Could it be the fuel pressure
regulator and how do you test it? Help!!
                           Nancy Barnes

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