93gen1st

So yesterday I got in my truck to leave work and drove about 10 miles and my truck started missing and popping and surging in and out. When it popped through the exhaust it would puff white smoke. Pulled off side of road and took fuel filter off which doesnt have 100 miles on it and clean as can be. Broke bleed screw loose and getting fuel when pumping lift pump. The truck will idle pretty good my question is if its not getting enough fuel blew injector tip or ip went bad. Any help is greatly needed.

cougar

I would think that a bad injector would make the engine run bad across the board. If it idles good, I would be thinking lift pump or air getting into the fuel line ahead of the injection pump.

j_martin

Who's Asap, and what does he need?

I agree, sucking air, probably before the lift pump. Could be the lift pump itself.

cougar

Asap, didn't he write fables?
A leaking supply line isn't readily apparent because the lift pump puts it under a vacuum, sucking fuel (and air if you have a leak) through it. What I have done is pressurized the fuel tank. Then a leak may show up.
The lift pump, though a great simple little pump are prone to fail in ways that are down right sneaky. Like internal leaks.

93gen1st

Sorry for the asap. This truck is my daily driver so I was just panicking a little. I have replaced the lift pump and the fuel line from tank to the pump still no change. If you hold throtle down it surges in and out and pops through exhaust with white smoke. Cracked each injector line loose with truck running and each one had bubbles for a few seconds before any fuel shot out. I also took a heat gun and all injectors are all within a couple or 3 degrees of one another. What next ip? Thanks for replys really use the advice

fatt

I'm betting something in the IP broke. Sounds like exactly the same thing my 91.5 did a couple years ago. Ended up being a bad IP, but not sure exactly what broke. I took it almost all the way apart and didn't see anything broken but a new (to me) IP fixed the problem. I can't post the vid from my phone but if you search "problem with 1991.5" on YouTube you can see a video of my truck's issue.

cougar

As you cracked each injector open, did you notice and difference in sound between each cylinder?
You need to find out were the air is entering into the pump. Sometimes a leak on the supply side can be hidden and very difficult to find. You might want to bypass your fuel tank and feed the lift pump directly from a container. That will eliminate that section as a possible cause. The drive seal in the injection pump can introduce air as well as leak fuel into your crank case.