Your going to have to do a little testing. I'd still have to use a gage and check fuel pressure. Not only check for correct pressure, check that the pressure will hold for a bit, with everything off. If the pressure drops like a rock, there is a pressure leak. One place you check for a leak is the fuel pressure regulator. If the vacuum line has gas in it, the pressure regulator is faulty.
Next, at the coil side of fuel pressure relay, dark green wire with whit tracer is voltage, comes from computer. The black wire with white tracer is a chassis ground. Unplug the relay when problem is ongoing, use a testlite between terminals B3 and A1, engine cranking, the lite should come on.
Also, when the problem is ongoing, besides fuel, are missing spark at the plugs or injector pulse?
Wednesday, September 17th, 2014 AT 2:28 PM