Lately my fuel economy has been in the dumps no matter what the driving condition or if I drive hard or soft. I have an 07 Screw 4x4 5.4 on 35s with magnaflow si/so exhaust, aem brute force intake, and sct tuner with custom tunes. All mods have been the same for the past year and my fuel economy has dumped from 14-16 down to 11-12. it is killing my wallet and the result is about to be a set of orange and black signs in the windows. can anyone possibly give me advice on something to change or something to add to help my problem? i have considered changing the exhaust to a more free flowing dual setup but not sure if that would help or hurt.

thanks in advance for help

mac

 

Depending on the miles i would do the fuel filter, clean the MAF sensor, and it may be time for o2 sensors. Also maybe dump the intake and do the Gotts mod. Have the plugs and COPS been changed?

 

51000 miles. fuel filter gets changed next week. nothing else has been changed but it has been to the dealer for the problem and they said everything checks out. and i havent thrown any codes thru the tuner which would indicate a problem

 

Adding more mods is not going to increase your mileage. How many miles you have?

Could be time for a good servicing.

 

51000 highway miles

 

I had the same issue and I changed my plugs, COP's, cleaned MAF, throttle body, changed camshaft sensors and fuel filter and mine went up to 15.5-16 for the last week and half. Of course just 2 days ago my truck took a **** but that's another thread I started.

 

Clean your MAF sensor to begin with, Also take it to the ford house and let them do the Fuel system cleaning ( i think its called the motorvac service). If you decide to do it i would wait until the new fuel filter is on. Also are you sure you are running pure gasoline? If its contains Ethenol that is the reason you mileage took a dump.

 

Oiled air filter? Clean the MAF.

Induction service is either Motorvac or BG.

 

I'm willing to bet on a nasty fuel filter. Hopefully that's the cause.

 

did it go down all at once? could be bad gas I rember one time in my last truck I got some bad gas it made it run really bad and mpgs dropped a bit

 

I wish it had been for just one tank but it has been ongoing for months and I have filled up at multiple different stations. Thursday I am having the fuel filter changed and also I am going to hook up my GPS to make sure my speedo is accurate. I will post if it causes any change from just the fuel filter. If that doesnt work then off to the dealer to get all cleaned out.

thanks for the advice!

mac

 

The 35's ain't helping either! Go down to a 33" tire if you can stomach the downsize. Maybe a light P rated tire also. Try some Techron fuel injector treatment after the filter change.

 

X2 on the Ethenol. Everytime I have had to run ethenol blended fuel I have lost 2-3 miles a gallon. I all try and run regular gas

 

Well if his area is like any of the surrounding states in northeast, you won't find gas without at least 8.2-9.8% Ethanol mix so you have NO choice.

 

thats the problem here in Wisconsin too...