Fuel Pump

[zgraham]

I think my fuel pump is going out. Last week the truck started losing power at 70. I would give it gas and it would sputter a little and take off. I stopped driving the truck until last night. The truck started having the same problem, only at 60 this time. I am new to fuel injection and figured it was a fuel problem. The truck starts and runs fine under 50. Am I right to assume this? Also, which is the easiest way to change the pump, drop the tank or take off the bed? Thanks for the help.

 

[Horns]

What year is your truck.

You need to check fuel pressure before you change the pump. You also need to check throttle body gaskets.

This could be a fuel or a timing issue. Get a repair manual, and study it. Learn how to diagnose the problems so that you're not wasting money on new parts that you don't need.

If you do end up needing to change the pump, lifting the bed is the way to go.

-via Mobile

 

[zgraham]

It is a 95 K1500 with the 350 tbi.

 

[98_k1500]

+1 on lifting the bed instead of droping the tank if it needs a pump. You will need a inline fuel pressure gauge to diagnose the problem, one that installs in place of your fuel filter.

 

[zgraham]

Any recommendations on brand of gauge? Do they carry them at the local parts house? What fuel pressure should the truck have?

 

[zgraham]

The check engine light isn't on, if that matters.

 

[98_k1500]

You should be able to go to oreilly's or autozone and rent one. Just put a deposit down and get your money back when you return it. 9-13 lbs is the stock spec, they run better at 13-15 psi tho. The injectors don't like to spray a nice pattern when you get in the low end of that range. If you don't have enough pressure, crimp off the return line (where it is rubber) with a pair of vice grips (or otherwise make it unable to return) and see if your pressure bumps. If it does, you need a regulator rebuild. If it does not (and it probably wont), you need a pump. Its worth checking before spending money on parts you don't need tho.

 

[TheTitan97]

I can hear my fuel pump whining every so often and its hard to start occasionally on my 4.3. I notice a really slight increase in power when the whining stops. you can really hear the whine when I fill up the tank. and my fuel gauge hasn't worked for the past 2 years, and I think on my 97 the sending unit is built into the pump. but anyway defenitly check pressure first. that's a lot of money to spend and time to replace it for it not to do anything.

 

[Horns]

Get an Actron unit. One with the GM adapter can be found for around $25.

-via Mobile

 

[Horns]

Sorry for the double post.

http://www.actron.com/product_detail.php?pid=16175

This is the one you need. I guess they cost more than I thought. I picked mine up on Ebay for $25 a few years back.