What would cause no fuel pressure after working on fuel regulator

tautog

I own a 2001 blazer 4.3lt 4 door 4wheel drive. I was having a hard starting problem several attempts to start before it would run on a few occasions it would back fire through the intake manifold. Researching pointed to fuel regulator. Put fuel pressure gauge on key on engine off got 55 to 60 psi it would drop to 48 or so. Changed fuel regulator (inside intake manifold) Inside the manifold it was pretty carbonized except under the regulator so I thought this was most probably the problem. When everything was back together I had no fuel pressure. Even though I could hear the fuel pump with the key on. I thought since the pump was on the old side maybe I could hear it but it wasn't pumping. I dropped the tank and changed the pump and fuel filter. Put pressure gauge back on and no pressure (0psi). I can hear the relay click and the pump. What did I overlook or screw up??

thecardoc3

Pull the tuner valve at the top of the intake and take a look inside the manifold to see if you have a leak in the injector assembly or its connecting line. Take note that you may have been pumping raw fuel into the intake which could end up on top of a piston and hydro-lock the engine if you attempt to crank it. Also note your engine oil level as fuel that does get into the cylinders will slowly work past the pistons and end up in the oil diluting it.

mmcleod1

I have a 2003 chevy blazer 4WD, when I press on the gas, it shuts off, the fuel pump, fuel filter, crankshaft sensor and craftshaft sensor, all has been replaces, what else can cause this problem

tahoelt10

Check volm manifold w/sensor

thecardoc3

tahoelt10 said:

Check volm manifold w/sensor

The valve oil lifter manifold is used on engines that employ displacement on demand and does not apply here.