hi again and thanks for answering. well it is EFI-v6 2.9 engine the truck run fine the only problem is when starting the truck sometimes it takes 2 or 3 tries then will start .as for the fuel pressure am going to check to see what's the pressure .
Before starting, when you turn the key on, the fuel pump should run for a couple seconds to pressurize the lines. One thing you can try is turning the key off and on again a couple times to make the fuel pump work more. If you can hear that, you will notice the pitch of the pump drop as it builds up pressure from low to high. If the engine starts easier after this, either the fuel pump is weak, or the pressure regulator is leaking.
When you check the pressure, you can again do the key on/off cycling, but leave it off afterward. The pressure should build up to around 40 psi, and hold. If it drops quickly, then the regulator is leaking the high pressure fuel to the return side. It's also possible that the pump is leaking, but I don't see that very often.
Hi again well I check the fuel pressure today. I turn the key on and off and I notice the pressure was trying to go up. but it show less than 10 lbs with
the engine off .but when I try with the engine running was showing around 28and 29 lbs and when I turn the engine off the pressure was dropping fast to 0 . please advice .
I've seen both weak fuel pumps and leaking pressure regulators doing that; one of them is not holding pressure. The regulator is the easier to replace, so I would start with that. I think on your engine, it's located around the front passenger side of the intake manifold. It has the return fuel line attached to it.
Also, with a truck that old, you might want to replace the fuel filter just as a matter of course if that hasn't been done before.