Hello all I am new to the site hope you guys can help.I purchased a 92 Laredo 4.0 auto with 18x,xxx miles on it. New plugs,wires,cap,rotor and fuel filter when I got it home. It had a rough idle when cold that's why I gave her a little tuneup. Ran great tho no issues at all and when it warmed up idles fine. Rpms would drop to like 500 when you came to a stop but would pop right back to 750rpm. I went out to start it the other morning and all she would do is crank and crank. I checked for spark seemed a lil weak so I bought a new coil and that brightened that up. Still no start tho so I checked fuel pressure and it squirt out strong.. pulled a plug and gas wasn't an issue. So not knowing what else ta do I changed the cps thing and still nothing. So I start checking things again,check rail for fuel pressure and it just dribbles out,no pressure. Had pressure earlier but not now,cycle key a few times and still no real pressure. Ok so im thinking fuel pump even tho I hear it coming on maybe theres a clog or something.I disconnect fuel line at the filter to see if she squirts out fuel and she does just fine but at the same time the damn jeep starts right up and runs for a few seconds meanwhile im pumpin the fuel into a gas can. HOLY CRAP that's awesome. I reconnect the fuel line to the filter and tell wife to crank it and nothing she wont start just turns over,what the hell. I check the fuel rail and shes got plenty pressure gas squirtin over passenger fender lol. Crank it again and still plenty pressure. So I go back under and undo fuel line at filter again and she was under pressure and made a hella mess but I was countin on that. I held fuel line into gas can and wife turned key and damn thing started again ,ran a lil longer I tried hook up fuel quic but quit before I could slide it on. So does anyone know what the heck is happenin here,pressure regulator my quess but tired just throwing money away. Any help would be awesome thanks.

 

I agree with checking the fuel pressure at the rail before spending more money on parts.

 

That implies at least some pressure, but agree to have that verified.