Hard start, acts flooded, turn key a couple of times to build fuel pressure then starts. Runs fine after

You should have the fuel system tested , fuel pump pressure an flow test . an static fuel pressure . There is a check valve in the fuel line inside the fuel pump module , this could be bad . You could try just turning the key to run, not start 4 or 5 times to see if this adverts this problem . This will build fuel pressure up , you see when you turn the key on the PCM/ECM -engine computer energizes the fuel pump for two seconds building fuel pressure .

You may need someone to help with this, or not.Turn off the radio and any accessory that will interfere with hearing the fuel pump. Turn the key to the on position,the fuel pump should turn on for a couple of seconds to build fuel pressure, and then the pump will shut off. Turn key off. Turn the key on, the pump will do the turn on and off again. Do this about 5 times. Do not turn to the start position until after the 5 times of building the fuel pressure up in the lines. After the 5th time, turn the key to start the vehicle. If the vehicle starts, then you're loosing fuel pressure when it's not running. Most cars have about 60 psi of fuel pressure. You'll need a fuel pressure meter to check it.

Have a test done on the glo-plug system as it appears that they have burnt out and are not pre-heating the cylinders or providing a source of ignition for the atomised fuel from the injectors

The problem on your vehicle is much more likely to be the oil pressure sending unit ore the fuel pump relay . The way the systems works is the fuel pump is supplyed by the fuse box fuse #9 but the cirrcuit splits and goes to the oil pressure sending unit in case the relay fails when your drivering the fuel pump will still have a power supply its stupid but its a safty thing that was mandated. If the fuel relay is NG the vehicle will still start but it takes the engine some time to build up enough oil pressure to trip the switch inside the sending unit to send volatge to the starter . Witch means slow starts long cranking times I would check the fuel filter first but realsticly if you don't know if the fuel pump has been replaced or you haven't done it your self this is vary likely the cause of the problem . If you have then try the oil pressure unit

REPLACE FUEL FILTER,CHECK FUEL PRESSURE, SHOULD BE SHOULD BE 9 - 13 PSI TBI FUEL INJECTION AND 55 - 61 PSI MFI FUEL INJECTION.WHEN YOU TURN ON IGNITION WITH ENGINE OFF.LET FUEL PRESSURE BUILD UP AT FUEL PRESSURE GAUGE TO CORRECT PRESSURE THEN TURN OFF IGNITION SWITCH. IF FUEL PRESSURE DROPS VERY FAST OR LEAK DOWN IN 10 MINUTES.YOUR FUEL PUMP CHECK VALVE FAULTY IS BAD.FUEL PUMP NEED REPLACING.BE SURE FUEL INJECTORS ARE CLEAN THEY WILL LEAK DOWN FLOOD ENGINE FOUL OUT SPARK PLUGS.

If it acts like it is flooding while idling, but it runs fine on the road, it could be running too rich and flooding it out due to leaking injectors, bad fuel pressure regulator, or excessive fuel pressure.

I would start by replacing the Fuel Pressure Regulator since it doesn't cost as much as the injectors.
Check your fuel pressure using a Fuel Pressure Check Gauge to see if the fuel pressure regulator is maintaining the proper pressure.

Vacuum is attached to the Fuel Pressure Regulator to control system pressure. When the fuel pressure regulator is not functioning properly it causes the fuel pressure to be above normal operating pressure. This condition causes excess fuel to be injected causing a rich mixture that produces black smoke.

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It sounds like a faulty fuel pressure regulator. When you turn the key to the on position the fuel pump starts for an instant to build pressure in the fuel line. If the pressure regulator has allowed too much leakage since the last start then the fuel pump does not have enough time to prime the line. The fuel pressure will still measure ok when the car is running because the leakage is very low. Try turning the key off and on a few times prior to starting and see if the extra pump priming steps help. Also check the vacuum line to the regulator because it needs vacuum to work correctly.

A very common problem on the 99 S10 is a leaky fuel pressure regulator in the intake plenum.What happens is when the truck sits for a few hours or more the regulator leaks all of the fuel in the fuel injection system into the intake air plenum. This does 2 things, 1 it has no fuel pressure when starting and 2 it floods the air intake with raw fuel. Sometimes if you turn the key on wait 3 seconds then turn key off then turn key back on and just turn key to crank starter for a split second and wait 3 seconds.do this 3 times to repressurize fuel system then crank to start(you will hear fuel pump buzz each time you do this.also you may have leaky fuel injectors. Try to crank engine with the gas pedel to the floor. This will tell the computer to stop spraying fuel trhough the injectors and it will start. Joe ASE Master Tech

it does sound like the relay is working part time and not all the time...you might want to go ahead and replace it just to find out for sure.

A common cause for this, asuming no check engine light, is a leaking fuel ressure regulator. When they fail, they leak fuel into the vacuum line causing a very rich condition- basically flooded.
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