grrr...bad mileage..no codes

[914x4sport]

It seems like my trucks been really suckin gas lately...So i ran the codes on it with a code scanner...Nothing showed up except code 74 which is the Brake On/Off switch and thats just because I didnt hit the brake after the Dynamic Response Signal...What could be causing such poor mileage and not show a code? I dont know how to check the timing but I doubt thats it..It runs really smooth, just sux gas..Ive been running it conservative/average lately in hopes of saving gas but that doesnt even help, Ive even tried different octanes..Im at about 110 miles of travel right now on a hair below half a tank. The second half always lasts longer too..Im expecting about 275 miles out of this tank..At 19 gallons thats only 14 mpg...And thats easy city driving and some 65 mph highway..I know this cant be average..What can I do to improve it? I have a k&n drop-in and basically wide open exhaust, shouldnt that improve my mileage? I replaced the O2 sensor not long ago, and that didnt show up on code so it cant be that..Any help please? I also noticed that only after hard driving(mudding) or after alot of highway driving,then immediate city driving(and generally only on hot days) my check engine light comes on.But it shuts off as soon as I restart the truck. ANYONE that has experienced any of this please respond, I understand if noone knows what Im talking about thanks...
Jeremy

 

[mdrut]

Hey Jeremy, did the poor milage start about the same time as you noticed the driveline noise??could you have some brakes sticking or maybe the t-case is still engaged?? I did reply to the balljoint post, just not showing in the replies colum..

 

[Nonoy]

How about cleaning your MAF sensor? I always do that when I noticed that my gas millage is bad. After cleaning, I reset my computer.

 

[914x4sport]

possible answer...

Well this may not answer everything but might explain a little of my problem...those of you that were at Bubbas the first F.E.C. meet may know what Im talking about...The first time I went to bubbas I didnt do any real mudding, but I did enough to kick a bunch of mud onto my exhaust pipe...As the mud burned it smelled pretty bad. So when I went home I made sure to rinse off the underside to make sure all the mud was off the exhaust..Well the second time out at bubbas I sank pretty deep.And my engine was off for a second(dont ask why I shut it off I just did, then turned it back on) After I got home and couldnt take the burnt mud stench any longer I rinsed off the underside of the truck, exhaust and all, well now everytime I start the truck and it warms up it still stinks of burnt bubba-mud..So what Im thinking is a bunch got in the glass pack(which Im assuming now is a mud-pack) and is burning off from the inside.While this is happening I think my O2 sensor might be gettin all crazy.Just a theory, my O2 sensor is new, but the mud fumes may be causing it to act erraticaly maybe burning and causing some deposits to form....I dont know..It didnt show up on the codes but does that mean it cant be acting up? Probably end up getting a new OGS next step is the FPR. And I gotta still clean the MAS. Im feelling SOL but Im sure itll all be AOK. he he

 

[FMExplorer]

Jeremy,
You probably already factored this in, but - you have bigger tires now. If your odometer says you went 250 miles, you really went 275 - hence your gas mileage will be 10% better than your calculations. Otherwise I have no clue

Jon