Fuel leaking into vacuum line on fuel pressure regulator

It's located on the fuel rail and has a vacuum line going to it.

When you had the fuel pressure tested did it hold pressure with the key off or did the pressure drop off?

If it dropped off I would bet you have either a leaking fuel pressure regulator or a bad fuel pump. Fuel pressure needs to hold steady especially on a hot engine in order to prevent the fuel in the fuel rail from boil over.

I think the 99 has the external injectors. If it does the fuel pressure regulator is located on the drivers side of the engine about in the middle of the fuel rail. There will be a small vacuum hose attached to it. remove the vacuum hose and see if gas comes out. If it does the regulator is bad. If it doesn't I would check the pump next.

There is no charcoal filter on the return line or the pressure line. The charcoal canister is part of the evap emissions system and will rarely if ever effect the starting of the vehicle.

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If it's not leaking fuel under the vehicle, the problem could well lie in a faulty Fuel Pressure Regulator.... If the rubber diaphram in the FPR becomes compromised, your described symptoms appear due to fuel leaking into the intake and not leaving the fuel line w/ injectors with enough initial pressure to instantly start the car.
Simply remove the vacuum line which is connected to the fuel pressure regulator then insert the key and turn to the "run" (not "crank") position. If fuel squirts out where you disconnected the vacuum hose, then this is definitely your problem. Good Luck!

You may have a leaky fuel pressure regulator located on the LH side of the engine on the side of the fuel rail. The internal diaphram can leak fuel which then gets into the vacuum line attached to the regulator. From there the leaking fuel travels through the line and gets into the intake manifold causing the motor to be slightly flooded when you restart it. The regulator is round, about 1-1/2" diameter, and about that long and has a small 1/8" vacuum line attached to it. After the engine has been off for a few minutes if you remove the vacuum line from the regulator and find even a trace of fuel in the line then you've found your problem. Typical symptoms for a leaky regulator are: Starts fine cold and will restart fine warm if the engine has only been off for a minute or so. Restarts hard warm if the vehicle has sat for several minutes or up to an hour. May produce a bit of black smoke during the warm/hard start.

Remove vacuum hose, find schrader valve and bleed off fuel pressure, pull out lock ring, remove regulator, install in reverse

SOUND LIKE FUEL FILTER STOPPED UP.WEAK FUEL PUMP.CHECK FUEL PRESSURE.IT SHOULD BE 60 TO 66 PSI.ALSO CHECK VACUUM LINE GOING TO FUEL PRESSURE REGULATOR.MAKE SURE ITS GETTING VACUUM.IF YOU GAS IN VACUUM LINE GOING TO FUEL PRESSURE REGULATOR.REGULATOR FAULTY.IF YOUR ENGINE IS 4.3 FUEL PRESSURE SUPPOSE TO BE EITHER 41 - 47 PSI AND 58 - 64 PSI

Remove the vacuum line from the fuel pressure regulator and inspect for fuel leaking into the vacuum line. There should be NO fuel.
The regulator is located on the upper intake manifold and is easily accessible.

Release fuel pressure by removing fuel pump relay and turning engine over to release pressure. Place a rag to catch any fuel under regulator Fuel pressure regulator has a locking clip pry clip off remove vacuum line pull regulator out with twisting motion,replace fuel pressure regulator install clip connect vacuum line install relay. Check for leaks,your done.

your fuel pressure is suppose to be 60 - 66 psi. first replace fuel filter.and check vacuum line going to fuel pressure regulator.make sure vacuum is going to vacuum line.if changing fuel filter dont help. fuel pump could be faulty.

The fuel pressure regulator is located on left side about midway of fuel rail. It has a small vacumn line cnnected to it. The diaphram can leak causing hard start after engine is warm.