Hey folks...friend of mine has a 94 F150 with 5.0L Fuel injected engine that won't start. He recently installed a rebuilt long block and when the mechanic started it there was popping in the exhaust. He fiddled with the distributor and got the popping to go away but the truck ran with a choppy idle as if it were missing out. The mechanic went on to other projects. My friend backed the truck up about 30 feet and said the engine was running very quietly but began to idle rougher and rougher, then died. Now it will not start at all. We installed a new distributor to no avail, then checked the codes. It passed EVERY code test...no malfunctions indicated. The coil checks out fine and there is fire at the sparkplugs. There IS a strong gasoline odor as the engine turns over and tries to fire...with the throttle body butterflies held wide open. Use of starter fluid once resulted in a HUGE backfire. My question is about the fuel pressure regulator. If you suck on the vacuum line attatched to it you cannot hear it move in any way and can faintly taste the gasoline. If this regulator is stuck open, will it cause the injectors to flood the cylinders due to abnormally high fuel pressures? Any other suggestions??? Thanx for any help!!