Quote:
Originally Posted by Baz
With the help of my mechanic, we ruled out the fuel pump.
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(scattering the cards on the table here, to start over from scratch, if it wasn't confusing enough) 
If he jumpered the fuel pump directly that doesn't discard a blocked line at the tank, bad or intermittent FP relay/fuse, whatever controls the pulses (PCM? ECM?), or ASD(auto shut down) relay mentioned by Fred in another post.
Once had a Bosch relay on a '89 Golf that would overheat with random heat soak after stopping. Or it would not start randomly. Probably a worn pump was drawing too much current. A new FP relay fixed it.
The vehicle might have a bad park/neutral lock-out switch. Or brake switch which releases it. My '95 Subaru would only start in neutral and had to open up the console for the manual shift lock.
Wiggling it sometimes helped.
Another possibility is a bad crank and/or cam sensor. That is another signal required for the engine to start running.
A quality scan tool would show a lot. Especially any codes.
If you can get some "noid lights" at harbor freight if might cut down the diagnosing. Put one on a disconnected injector. They flash while cranking. That means the crank/cam sensor is good, ECM/PCM is good, and it's trying to spray gas. We will assume the timing is correct and not a factor. It would at least burp and sputter.
Then it's off to hunting down spark and actual fuel delivery.