I have trouble in start up. I drive a 1993 S-10 Blazer Tahoe. It is 4x4 with the 4.3 Vortec, and the automatic 4L60E. The problem is that it seems to have to turn over way too long before it finally fires up. And when in idle it sometimes acts like it is trying to die and then surge like it is catching it's self and reving up. I am slightly familiar with the Central injector unit.................the spider. Does it sound like the regulator is leaking preassure, could it be the injector unit it's self, or is it something else.

 

To diagnose a fuel system leak, you really need to monitor the fuel pressure once the pump is turned off. A leaking FPR will gradually bleed down the pressure in the supply line and may cause your hard start if there is little to no pressure.

Next time the truck sits over night, try turning on the key until you hear the pump shutoff, then try to start it. This will give the pump time to build up the fuel pressure before you attempt to start it. If it starts right away, then you have a problem with fuel pressure leak down. This can be caused by a leaking FPR or a leaking check valve in the tank.

I would suggest getting the fuel pressure checked and if a leak is detected, then pop off the plenum and pressurize the fuel system again. Look for leaks around the lines and around the FPR.

 

I would also look for a vacuum leak.