Barely any fuel pressure 92 lumina

92 Luminia 3.1L

Hi there - can anyone tell me what exactly would cause low fuel pressure? When I press the schrader value gas doesn't come spraying out, it somewhat pours out instead... I can hear the fuel pump prime up.. Could this be a bad fuel pressure regulator or fuel pump? Also would a fuel pressure gauge help me figure out what the problem is? I would greatly appeciate any information regarding this. Thanks.

Btw.. The fuel pump and fuel filter was changed about 4 or 5 years ago (30,000 miles or so ago) and I also just replaced the crank position sensor, ECM, and changed all the plug and plug wires last week (due to random no starts and rough idling) After that car started most of the time but still sometimes would not. When it would start it ran fine, and idled smooth. Last time it didn't crank (only turning over) I tested for spark - it was getting fire.. Only code that ever came up with was CODE 32 .. Today was the first day I could not get it started within 30 mins..

Oh and since I've been reading on here, the low coolant light sometimes stays on, could that be a problem?

The fuel pressure should be 31-34 psi, key on/engine off. You can buy an inexpensive fuel pressure tester at Advance Auto or Auto-Zone for around $30-$35. With the engine running and the guage attached, disconnect the vacuum line to the pressure regulator and the fuel pressure should spike to 40psi or so. If it doesn't then the fuel pressure regulator is bad. Also inspect the vacuum line to the regulator for fuel. If there is fuel in the vacuum line, the diaphragm in the regulator has a hole in it and fuel is being sucked through it. If disconnecting the vacuum line causes the pressure to increase, but it's still below the above spec, pinch the fuel return hose and the pressure should spike up. If not, then the fuel pump is shot, and even though it is operating, it's not providing enough pressure.

After the car sat overnight it cranked right up, and ran fine. I will test the fuel pressure next. Is there anything else that would cause it not to start sometimes even if I'm getting spark?

Sorry for my lack of knowledge, but my return line from the regulator seems to be metal.. How do I "pinch" it.. And the vacuum line you mention are the 3 lines that cluster together on top of the throttle body/intake?? I just bought a fuel pressure regulator and I'm going to test the pressure tomorrow. Today the car started 6 times and ran good..