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Charles, That buzzing thing is actually called a frequency valve, its controlled by the computer and it adjusts the fuel mix. It sounds like you have whats called a "rest pressure" problem. Thats when fuel pressure leaks back to the tank after shut-down. The most common cause is the fuel pump check valve. These are available separately, though you may have to shop around to find one. I don't know if the dealers carry them or not. The proper way to diagnose the system is to hook a special fuel gauge set-up and check the pressures, but it doesn't sound like you'd have one of those. The odds are in you favor that the check valve will fix it. You've got to jack up the car and remove the pump and work on it on the bench to change that valve. Its fairly self evident what you need to do, but be careful not to break the plastic fuel line. I hope this helps, Chris Bogue