I recently purchased a 96 f150 4x4 eddie bauer edition w/ a 4.9L 5 speed standard transmission in it. After previously owning a 93 of almost the exact same configuration (only exception is the 93 was an xlt and not an eddie bauer) I thought I knew what I was getting myself into, I loved the 93 and regretted getting rid of it, but I knew after owning that one that I wasn't going to get great gas mileage. 4.9L's just don't do that hot when it comes to fuel efficiency. The one I recently bought is getting 12 miles to the gallon consistently and it only has 70,000 miles on it. It runs great but it does have some trouble codes that are kicking on the service engine light, the codes are PO171 and P0174. Has anybody else experienced a problem like this with a 4.9L. I just wonder if the codes are linked to the poor fuel economy. My 93 got around 17 mpg. I jsut cannot believe the mpg out of the 96 is normal. Any information provided would be greatly appreciated, if I don't find a solution I think I'm gonna have to sell it.

Thanks,

metalman_ru12

 

check for a vacuum leak. what gears does the 96 truck have in the axles? what did the 93 have? has it ever been tuned up? with the age i would tune it up if it never has been.

 

I haven't run any official vacuum leak tests but have listened around the engine for one while it was running and can't hear any, I know that doesn't necessarily mean there isn't one. I do need to do a tune up and see if that helps. The performance of the engine wouldn't indicate that but at least if I do one I'll know for sure that's not the problem.

Thanks!

 

codes 171 and 174 are lean bank 1 and 2 codes. i would clean the MAF sensor and throttle body. also check for any air intrusion after the MAF sensor. also check fuel pressure, air filter and PVC.

a tune up is also a good idea. start with some cheap copper motorcraft plugs, good wires, etc...dont forget the fuel filter and maybe try checking the base timing. i try to include it in all my tune ups.

 

I'll try that if and when I ever get the time time. Thanks for the advise! What's the best fuel mileage you've gotton out of your 4.9?

 

mine? about 15 but my dad has the same truck as mine but stock and he regularly gets 18 mpg.

 

I'm hopefull to get this one up to 18 mpg, I can live with that. Thanks!

 

my 93 is pretty hopped up and i drive it like i stole it...hence my poor milage. heh...