betterthanwheaties

I'm not very good with words but here we go. My truck will start without issue 9 out of 10 times. The tenth time is just a dud usually. Anyway once it's running the rpms become very sporadic between 300 and 1500 rpms while I'm holding the brake. The truck sounds like it's dying then gets like super juiced and revs itself up. It usually can maintain this erratic idle while in park and neutral but when it's in drive or reverse it tends to die within 45 seconds unless I flutter the gas pedal a little bit. Already replaced fuel filter, fuel pressure regulator, distributor cap and rotor, upper intake gaskets, cleaned mass air flow sensor and replaced air filter. Kinda feel like I'm just throwing parts at it now. The problem does not go away once I start driving. It becomes worse. The truck will stop accelerating around 40 and when I hit the gas pedal to try and feed a little more fuel to the motor it makes a real low, hollow rumble. Any help/similar experiences are appreciated.

chris29445

Is it possible that your truck is "whistling" while doing this "sucking air" into a broken vacuum line?

Or could this possibly be a fuel pump failure