krodk

I have a 1999 Silverado Z71 (5.3) with about 220,000 miles on it. About a month ago it stopped running and I could not figure out the problem, so I took it to the local shop. Turns out the fuel in the tank was about 50% water. They drained the tank, put a new fuel filter on, and added new fuel. When I went to pick it up it ran, but terribly. The guy said to drive it for a few days, because there could still be some moisture in the lines. Between then and now I have not had time to mess with it, so it just sat. Now it starts, shakes and sputters, then dies. If I use the throttle when starting it will slowly sputter up then smooth out for a couple seconds around 1500rpm, then just drops off and dies. I just put new AC Delco plugs in yesterday in case the moisture fouled them out, but did not change the wires. This did nothing. The fuel pump is running, and I checked the pressure before taking it to the shop (50psi key on, 54psi cranking). I have no idea what to do now, and don't want to take it back in unless I have to. Any suggestions much appreciated! Thanks!!

justimagination

Go to Walmart or good auto parts store, get a bottle of " STABILL " which is for contaminated fuel . It's in a clear plastic bottle and is red in color. Good luck.
David g.

krodk

Thanks for the suggestion! I tried this, but unfortunately it did not work.

justimagination

OK, since you've already tried, I would take the fuel tank OFF, you should check the strainer on the bottom of pick-up. If it has the original fuel pump, it's probably a good idea to replace it. These trucks are prone to have fuel pump problems. JMHO.
David g.

meternerd

Can you pull the fuel line off at the engine? Put the line is a jar and see how much flow you get. Make sure it's clear and clean fuel. Could be that your fuel filter is plugged again. Pressure would be good but flow would not. Injectors could be plugged too. Basically, anything fuel related, but start with the easy, cheap stuff and work you way up to the hard, expensive stuff. You'll find gunk somewhere is my bet.