very bad fuel economy.

[sethc24]

Guys my truck is getting terrible economy about 200 miles a TANK!.

I looked underneath and in the engine valley ( fuel bowl etc.) And i found no leaking fuel anywhere.

Its a 2000 f250 extended cab shortbox, 6 position chip from tdp, 4" Tb exhaust, 6637 filter, weighs 6800 pounds with me in it. Has 265/75/16 tires on it.
Note the air filter does have some mileage on it. And it is a little bit dirty but even then i dont see how it could effect economy that much.

No check engine lights, This is driving normally/lightfooted. It is an automatic. Tranny fluid level is fine and pink. The brakes are not dragging, wheel bearings okay i believe. HELP!

 

[BigAlsPSD]

I would start by looking for leaking up pipes, boost leaks, and cleaning the EBPS and tube.

 

[4cstr]

What setting are you running in on your chip? Does the truck feel like its making power...or does it feel like a slug? I agree with BigAl on looking for boost leaks. Do you have a set of gauges? If so...are you making any boost or are EGT's running warmer than what would be considered normal for driving lightly daily.

And even though it not make a big difference...clean or replace that airfilter.

 

[sethc24]

No boost leaks. I got plenum intake inserts aftermarket boots, brass up-pipe donuts. The truck does feel like a slug no matter the setting. This is mostly driving in the daily driver setting. Yes i have gauges. Oh and i did clean out that tube and sensor.

 

[Curtis@Vision Diesel]

I would start with the air filter..If not just a guess. Could your fuel pump be going bad?? If everything else is up to par?

 

[Big Bore]

Change all the filters and oil, add injector cleaner to fuel such as BG44K, if possible drain filter bowl and fill with straight BG44K. Has the tank been cleaned ever? Mixing valve will clog sometimes.

 

[sethc24]

I just put on a Driven diesel pre-pump/tank mod kit. So mixing valve is deleted and i inspected inside of the tank and removed any chunkies. I am using pre pump filtration with a Baldwin spin on filter from the kit. Just changed engine oil/ oil filter, and fuel filter. Using motorcraft filters and oil. I drained the fuel bowl when i changed the filter.

Also i get no check engine lights under full throttle and i make 30+ boost.
So i don't think i have a weak hpop. How do i check if my fuel pump is going out? That is the one on the frame rail right?

 

[bad12jr]

100 psi fuel pressure gauge into the schrader valve on the fuel bowl.

 

[BigAlsPSD]

Super Duty's do not have the schrader valve like the OBS, but you can add one.

 

[Tree Trimmer]

but if you take a little rubber hose, bout 4 ft long, and hose clamp it on the drain tube from the bowl, and open the drain valve, you can read pressure that way.

or remove the tube from the back of the bowl, and attach hose there.

make sure to shut said valve when done.

 

[zilla68]

Guys my truck is getting terrible economy about 200 miles a TANK!.

I looked underneath and in the engine valley ( fuel bowl etc.) And i found no leaking fuel anywhere.

Its a 2000 f250 extended cab shortbox, 6 position chip from tdp, 4" Tb exhaust, 6637 filter, weighs 6800 pounds with me in it. Has 265/75/16 tires on it.
Note the air filter does have some mileage on it. And it is a little bit dirty but even then i dont see how it could effect economy that much.

No check engine lights, This is driving normally/lightfooted. It is an automatic. Tranny fluid level is fine and pink. The brakes are not dragging, wheel bearings okay i believe. HELP!

that's what my truck gets, and I just got it TO THAT POINT, was getting 125, hope you figure it out and let me know what you find

 

[littleredstroker]

Sound like mine when I'm ICP sensor went out. U sure CEL works?

 

[twelch3]

I would also check the MAP sensor and line to intake y.

 

[sethc24]

I have an ocr installed from Riffraff Diesel. The lines to the intake y are fine.

ICP sensor is that the sensor on the drive side oil rail? What am i looking for on it ?

 

[4cstr]

Yes. Check to make sure its properly connected. If you know of anybody that has a good working one...swap it out and see if it makes a difference. Without a reader its tough to know if the ICP is acting up.

 

[2000wa250]

you said you are running pre and post pump filters and the fuel bowl? why not delete the bowl if you are running spin on type filters? could it be that the fuel bowl is effecting fuel pressure? sounds to me like you have a restriction somewhere. Also check your EBPV, it might be stuck shut?

 

[sethc24]

My EPBV is deleted along with a blank pedestal. I only have a pre pump filter system.
I dunno if i have a fuel restriction. It sure lays the coal in my street tune from TDP if thats any indication. I don't know anybody with a working icp sensor. I think i might see though about getting a good scanner on the truck. Will i need some kind of data logging device to check the icp?

 

[littleredstroker]

turn ur truck on and while it is running unplug the ICP sensor on the head right by your lifting point. if there is no difference in the way the motor runs your ICP is bad. If there is a difference (notice rougher idle) ICP is good.

 

[sethc24]

ah okay thanks that is very helpfull.

 

[sethc24]

Okay unplugged the icp sensor while the engine was running. The engine bucked and started running rougher also triggered the engine light. So i guess the icp is good.