Low Power After Bad Fuel

levi1906 · Jun 29, 2013

Filled up with fuel the other day and the truck started running rough. Changed the fuel filter, ran good for a few miles, then started running rough agian with no power. I then drained the fuel tank(fuel looked terrible), and changed the filter again. Once again it ran fine for a little while then started the same thing again. Pulled filter again, it looked fine but I changed it again anyway. Drove up the road and the water in fuel light came on. Took it back home, drained the tank again, wiped it out spotless clean, ran the pump until I got clean fuel at the bowl and once again a new filter. No change except the light went off.

Next to no power, it's not smoking at all, no check engine light, and under load it seems to have a "miss" sound that can also be felt as a kind of vibration in time with the sound. Also, it seems to have a vibration around 1000-1300 rpm that wasn't there before, but sounds fine. Also sounds perfectly fine at idle. I"m thinking a bad injector possibly? Any thoughts?

JLDickmon · Jun 29, 2013

possibly.. or a hunk of snot or something in the ports..

I'd run a can of Diesel Cleen or Sea Foam through it before I got my panties too tightly bunched..

BlueScab · Jun 29, 2013

Possibly clogged pick up screens in the tank?

levi1906 · Jun 29, 2013

I did run diesel kleen through it. With no affect. Also the pickup screen was cleaned while I was cleaning the tank

POWER-STRUCK · Jun 29, 2013

what brand filters? any chance that the bottom of the old filter is stuck under the new filter preventing the standpipe from opening all the way?

levi1906 · Jun 30, 2013

No I cleaned everything out of the fuel bowl

ghohouston · Jun 30, 2013

levi1906 said:
I did run diesel kleen through it. With no affect. Also the pickup screen was cleaned while I was cleaning the tank

there are two "socks" if you will, in the fuel sending unit, that can get stopped up as hell, not the large metal screen at the bottom of the unit

Arisley · Jun 30, 2013

Yep, the "mixing chamber" Where hot return fuel that is full of air is mixed with nice clean cool fuel being picked up out of the tank. There is also the "duckbill" that is actually meant to be a secondary pickup. Only problem is that when it get old, it gets stiff and brittle. Meaning when you drop below a quarter tank, the "duckbill" is sucking air into your fuel system.

Hutch and Harpoon fixes all of this issue.
http://www.guzzle7pt3.com/hutch.php

First mod I did to my truck.

levi1906 · Jul 1, 2013

I just pulled the sending unit back out, cleaned the socks in the mixing chamber. very dirty! made me kinda hope full that this would fix things. however it did not.

im going to get the parts to rig up a fuel pressure gauge just to see what im getting.
should be close to 60psi????

I tried taking a temperature reading of the exhaust ports looking for a dead cylinder but couldn't tell much.

it seems to idle just fine so im wondering if that would even tell me anything?
could an injector go bad and the truck still idle fine but run like crap from 1000rpms and up?

ghohouston · Jul 1, 2013

It is possible. And hey, you cleaning those socks, can only do you good, i have seen them cut power drastically on trucks before., and im sure youre quicker at dropping the fuel tank by now too lol

ghohouston · Jul 1, 2013

And yeah around 60 psi is good

levi1906 · Jul 1, 2013

Actually I pulled the bed off.

I didn't get a chance to put a pressure gauge on it yet. Hoping to get that done tomorrow after work.

Will getting a buzz test done tell me for sure if it is the injectors?