I came out to start my 98 Bonneville (non-supercharged) one morning and it would turn over but not start. I checked my fuel pressure which registered around 44 psi. According to my Chilton'* guide that'* not within the minimum spec of 48, so I changed my fuel filter (186,000 miles on it... yikes!). This helped some, but still no start and not within the minimum 48 psi spec. And actually after checking my pressure the next day it dropped to around 10 psi. I just changed the fuel pump and sending unit, but still no luck and still not within proper fuel pressure specs (back to 44 psi again). Don't know what'* going on, my Chilton'* manual suggests trouble-shooting the fuel pressure regulator (no kinks in fuel lines or leaks that I'm aware of either). I'm really new to this whole DIY mechanic thing and don't want to throw money away by buying parts that don't fix the problem. Could really use any and all help, I'm at a loss (and banging my head against a wall ).

Not even sure that the fuel system is the root of the no-start, which is what I'm really trying to address. A friend of mine said the way fuel injectors work is that if they don't have the right fuel pressure the solenoid isn't actuated and fuel never even reaches the combustion chamber. This is the main reason why I'm trouble-shooting the fuel system of the car for the no-start situation rather than other systems. Any incite? Thanks for any help.

Try this. You need to determine if the problem is fuel or spark. Pull out a spark plug and put it in the plug wire. Lay the plug on a ground and have someone turn the engine over. Watch for spark. If you have a spark then the problem is the fuel. If you have no spark it'* the ignition system.

I tried that in the beginning (guess I should have noted that). I got spark. Do you know anything about a possible malfunctioning fuel pressure regulator?

pull the line off the FPR and tell us if their is a smell of fuel there of it fuel comes out