could be your imrc hope you find out soon.

 

Plain english is good. Maybe go back to stock with your tuner and try agian ???

I may grow old but, I,ll never grow up.

 

imrc stands for intake manifoild control rail. Makes you have bad gas mileage but does not effect anything other than gas mileage. pretty common on the 4.6 but i just replaced it on my 5.4 i hope this helps

 

What's the current odometer reading on the truck? Sounds like bad o2 sensor(s) and/or plugged up catalytic converter(s). But if you lost a quarter of a fuel tank going 16 miles then you got gas leaking out the fuel tank or the hosing that brings the gas up to the injectors. Maybe a leaking fuel rail. Check that stuff out before your truck explodes.

 

IMRC=Intake Manifold Runner Control

Wasn't aware that any of these engines had an IMRC, as they are all single runner manifold systems.

The IMRC comes into play on the Ford 2.5L duratechs, had been pretty much abandoned for oval port intakes by 2001.

 

Ok guys well ill try to make it a little clearer,my 4.6 2007 single cab is wasting alot of fuel and does not respond the same.I already changed the spark plug boots,changed spark plugs and changed oil...my mods are k&n cold air intake,magnaflow exhaust,and a performance tune...it is getting confusing to me because it is a fairly new truck for it to be catalytic converters or something bigger,idk what.this could be...and the way I measured the mileage is I filled my tank up and set the truck on trip,by the time I hit 16.5 or so miles I had lost a quart of gas,I checked for gas leaks or any smell of some kind and nothing,I've been doing this often I don't wanna let my gas drop for more than half a tank,this past Thursday I added a fuel cleaner nd the best it did was 17.2 miles before it wasted the quart and it continues the same way,....can u guys help?? I don't want to sell my truck plz

 

Dude...Quart or Quarter????? you're messing everyone up. There is a HUGE difference...A quart of gas in 16 miles is probably about right...even though I cant figure how the hell you can measure that.....A quarter tank of gas in 16 miles is horrible. Return the truck to stock and see how it goes. That would be the best place to start.

 

Sorry bout that yea a quarter of gas,lol changing it back to stock??? Hmmm what about retuning the truck??? It's not the spark plugs or the boots,i haven't tried cleaning the maf sensor,and no check engine light comes on...that's y I made this thread

 

And still we are asking... 1. Are you using a quart of gas in 16 or so miles? 2. Are you using a quarter of a tank of gas in 16 or so miles? Pick a number, 1 or 2. If you pick number one, most of us wish we had your problem.
If you pick number two, then yes you have a problem. One person suggested resetting your programmer/tuner back to the factory setting/tune. It is possible there could be an issue with the tuner settings. Also you mention the truck isn't very old, or is "new" to you. Is it under any kind of warrantee? If so, take it back to the dealer and have them check it out.
Just a thought, after driving the truck, check to see if either of the rear wheels feel hot to the touch. There have been a few trucks that have had one or both emergency/parking brake stick in the "on" mode, without an indication on the dash.

 

Nice info,I will check that but yes.Problem number 2 is what I'm dealing with,unfortunatly I have no warranty but the truck barely has 42,xxx miles,pretty new to b the sensors or catalytic converters to me no??