[Longhorn321]

Originally Posted by bwood

2000 3/4 will be the 88-98 body with the Gen I Small Block Vortec. The fuel pumps are a weakpoint with these trucks. Try taking a rubber mallet and smacking the bottom of the tank and then seeing if it tries to prime when the key is on. Pulling the bed is the common way to change the pump. While the pump is out/you are looking at connections, inspect the connector to the pump, they are known to have burned/bad connections. The fuel pressure test port is located on the driver side of the intake on top of the larger steel line feeding into the injector assembly. These trucks don't have a fuel rail like your used to, the feed fuel into a common injector assembly that contains a electric solenoid valve for each cylinder and a line from each solenoid to a poppet valve that contains a spring loaded check valve that opened with pressure to create the spray. If I remember correctly, it was called Central Sequential Fuel Injection (CSFI). You should be able to turn the key on and hear the pump run for about 2-5 seconds. This also would not set any codes. The fuel pressure spec should be around 63psi running.

I figured someone with some specific knowledge would speak up. Thanks bwood for some interesting information. I looked that CSFI stuff up. That is some weird chit to me.