Wow...so my misfire is mostly taken care of. Still has an intermittent in probably only one cylinder because every once in a while at a slow crawl I can feel the car shake just a tad. But I decided before running seafoam through the injectors, I was going to change the fuel filter as it was obvious this hasn't been done in a while. Since I had to relieve pressure at the shrader, I figured, heck, why not test the fuel pressure?............................yeah, that ruined my day.

The youtube video I posted says it all:
http://www.youtube.com/watch?v=Pw3TtzAxPGc

Okay, so what gives? Idling it holds at 31-32, dropping off to around 29 under load. RPMs topped off at around 4000. I know I should go do WOT, but it was dark outside. I don't think this is normal fuel pressure. Fuel lines charged with the car off the fuel pressure never topped 34 psi, even turning the key multiple times. Pressure did NOT fall after charging, so no leaks. Regulator? Fuel pump problem? What do you guys think?

 

I think it has to be the fuel pump and nothing else. Once you get to it, it isn't hard to change.

 

Trapdoor method or drop the tank? :'(

 

The pressure is barely bumping up under load. Since you're in park/neutral the only load the engine is seeing is from spinning up its rotational mass. As soon as it's revved up (or close too) the manifold see's vacuum again.

The pressure does appear to be low, when you rev (or remove the vac hose from regulator) the pressure should blip up to >40psi, and around 35 at idle.

Replace your fuel filter, check the regulator for a broken diaphragm, cut the access panel and see if your lines have leaks anywhere or anything, if not might be time to change the pump.

 

Were you testing the idle fuel pressure with the vacuum line connected to the fuel pressure regulator, or disconnected? Start with the vacuum line disconnected - hold your finger over the end, to prevent a vacuum leak. Pressure with the vacuum line off should be 43.5psi, with anything from 41-47psi within GM specs. Reattach the vacuum line. Since appears you have a stock cam, the fuel pressure should drop about 8psi from the "no vacuum" pressure. In any case, 30psi seems too low, but check it without the vacuum line connected.

 

I didn't. I was more interested in a real WOT test. After seeing the pressure so low to begin with, I wasn't really sure it was necessary to do any more. Either way, something needs to be fixed and replaced.................again. Lol, I got this car so I could learn how to work on vehicles. Wow...be careful what you wish for! But really, it is fun to work on. I'll retest later this weekend and see what happens.

Oh, and btw, the fuel coming out of that fuel filter.....man. I am not sure it was ever replaced and I am at 159xxx. No wonder the injectors might be clogged.