1999 Chevy Silverado Fuel System Problem?

[bostonsportsfan17]

Ok I cannot figure this out....I have a 1999 Chevy Silverado with a V8 4.8L with 113000 miles. At first the fuel gauge stopped working properly which was a sign of the fuel pump going, also when I turned the igniton key halfway to turn on the electrical and etc. I could hear the pump turn on but than there would sometimes be a LOUD quick knocking or more of a purr i guess all the way from the fuel tank up the fuel line and to the engine. If you put your hand on the fuel line you could easily feel it. This was a very abnormal sound and sometimes people standing 50 feet away could hear it and would look over. The few times that this knocking does not exist the truck is very hard to start and will take about 15-20 seconds or more to turn over. Also, randomly the truck will not pick up rpms right after being started..even on really warm days. I did a pressure test and it tested fine but Eventually the fuel pump broke on me 2 weeks later when I was at school..over 100 miles from my house. The tow home was way to much $, and I found a local garage to do it for $600 including the pump for about $300. After that it ran and started perfectly for about 400 miles and than it all started all over again except the fuel gauge still works fine. Other things you may want to know are that a new fuel filter was put in about 1500 miles ago and the truck does have an after market KN cold air intake. Please help me, Thanks
the spark plugs were replaced about 1500 miles ago, so it is not the spark

 

[razlan]

We always replace the fuel filter when the pump is replaced.
As a plugged filter can take out a pump .
And did they look in the tank for dirt .
Have seen this happen as well .
Customer has replaced fuel pump and a short while later it stops working.
When we pull the tank we have found lots of dirt and sludge in the tank.
Fuel pumps dont like this.
Check the fuel pressure to start.
May have a different problem this time.
Auto tec..