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It seems like you have covered the basics with fuel and spark. The next logical thing to test is timing. I do not know what this vacuum reservoir that you are speeking off is but that valve my be normally open and powered shut. Oh yeah, just because you have fuel pressure doesn't;t mean you have injector that are opening be sure to test these during your diagnosis.
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This valve sounds like the evaporative emissions system and the valve that you are describing sounds like the canister purge valve the is probably ground switched from the ecm it scavenges fuel tank fumes and puts them back into the combustion chamber via the intake. Check timing and injector pulse.
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problem partially resolved. Did not look at timing as all plugs firing when placed on the manifold 1-3-4-2. After removing all injectors and watching them operate and spray fuel (which I presumed was the case), then checked the air intake manifold wich appeared to be working, however the engine fired up when this was disconnected and was running ok. I heard a few missfires so I will be changing all the HT leads, dizzy cap and rotor. I will also be seeking a recon air intake manifold.