I've been searching the board on MPG topics (and their is a lot of them) but I came across alot of people saying the CAI's drop your MPG and some who say the opposite! What's the real deal fellas? Cause I'll pull that puppy out in a second to get 1-2 more MPG's!

Also it has a Flowmaster cat back, stock size BFG All Terrains (new) and 84000 miles. I'm having the plugs changed this week!

 

My $.02 -

I have an 03 with the 4.6L. In stock configuration it is almost not worth driving. poor acceleration, slow to shift etc. I did two things hoping to improve the mpgs (which in stock the best was 18.1 mpg). I bought a tuner and custom tunes, and a CAI. the tuner dramatically changes shifting, power etc. Like a new vehicle. The CAI works with that to supply more air for the changes in the A/F curves that the custom tunes have. Also the computer adapts to increased air flow. Having said that, here is the sea-saw between power/performance and mpgs...

Essesntially, more air means more fuel consumed = more power. I was thinking that more power on the same vehicle means less effort per unit of fuel to generate hp, therefore less fuel needed, hence the balance between power and mpgs.

I would have to say that I probably lost 1-2 mpgs. In stock, driving vey gently, the best was around 18 mpg - once. Most of the time it was 16-17. With the changes, I can do about 16.5 maybe a little more with summer fuel. Not so good with winter fuel. And if i get on it, then I loose more, of course. And since I have more power and better acceleration, I get on it more. My wife said she noticed a change in my driving style. Oh really?

Am I dissapointed - yes, but. it makes the truck worth driving. And there are at least two other mods to compensate w/out affecting the A/F consumption issue. One is electric fans which reduce hp loss to spinning mechanical fan. The other is an improved exhaust. There are still more, but I think that those will be my limits lest I seek a death wish from the boss.

So you need to ask yourself what side of the sea-saw you want to be on. If 1-2 mpgs is worth sacrificing over more power. Maybe with the 5.4 it is not necessary (power wise) and you could do with out it. In that case, I would look at the Xcal II and custome tunes from Troyer performance. Even without the CAI, you will see a huge difference in drivabiity.

let us know how you make out.

 

any of you that complain of the "performance" aspect of a truck meant to haul people and cargo, where do you all live and what kind of roads do you frequent? Why do I ask? I have a '97 4.6 4x4, and yeah, it's nowhere near as fun to drive as my Prelude, but that's why I have the Prelude. Also, I live in the City and I haven't been in a situation where I have exceeded 60 mph in about 3 weeks. Maybe that's why I am less displeased with the performance than some of you. I just don't understand buying a 5,000+lb truck and complaining that it isn't fast. I don't complain that my Prelude can't carry 2x4's.

 

True Story....This truck is a pig. It eats gas and doesnt even crap fertilizer. But I own one to tow and haul...I knew the mileage would be for crap when I got it.

Try removing the CAI and see how it goes for a few tanks. I bet you'll be suprised.

 

The subject is more along the lines of getting better fuel mileage.

I don't know about you, but I don't enjoy paying $100 to fill my Expy and I didn't buy this brick thinking that I was going to get +25mpg and be rewarded with $50 fill ups. So if I can find a product reasonalbly price that allows me to pick up a mpg or 2 and get better throttle response to boot I see nothing wrong in asking the fine members on this board for advice on which products will help me acheive this.

Thanks for the lecture though!

 

"I have an 03 with the 4.6L. In stock configuration it is almost not worth driving. poor acceleration, slow to shift etc. I did two things hoping to improve the mpgs (which in stock the best was 18.1 mpg). I bought a tuner and custom tunes, and a CAI. the tuner dramatically changes shifting, power etc. Like a new vehicle. The CAI works with that to supply more air for the changes in the A/F curves that the custom tunes have. Also the computer adapts to increased air flow. Having said that, here is the sea-saw between power/performance and mpgs... "

I guess "almost not worth driving" means something else to you?

 

Re-read post. Edited

And I guess if it meant to haul people and cargo and weigh more than a Prelude you can never expect if to have decent acceleration and performance? Then why is the aftermarket wasting their time developing products to do such things for these large vehicles?

 

the comment I was pertaining to was the guy who said the 4.6 stock is almost undrivable. I take issue with his perception of "undrivable" and the expectation before he stepped into the stock vehicle. Feel free to make your expedition an SRT-10, that's your choice. But my complaint revolves around the people that will complain to Ford that the truck is slow. It's a truck, not a hot rod. I blame no one that wishes to pursue turning their truck into a hot rod. That is not who I was complaining about. I think calling the 4.6 undrivable shows a remarkable lack of reasoning. Kind of goes towards the American mindset of wanting our cake and eating it too. We want to haul 9 people, 12,000 lb trailer and hit 60mph in 6 seconds with 25mpg and 75% resale value in 5 years. For less than $30,000. And we complain about any of the aforementioned dreams that the vehicle doesn't accomplish.

 

Point taken.

To each their own when he comes to expectations of what the 4.6 is capable of. You may find it adequate but someone else may not. I tested both the 4.6 and 5.4 in the Expy's and while they both were respectable in the git up and go department, I found once loaded with people and/or towing the 5.4 was the way to go.

Excursion with a chipped diesel. Except for the pricetag and the 6 second 0-60.

 

Thanks for some of the response guys! I also forgot to mention that I am running Royal Purple in the tranny, t-case, front and rear diff and eng oil!

But I think the killer for me is living in Alaska, I'm on an island with one main road thats 10 miles long. So when I get on it sometimes and I reset the overhead computer and by the time I'm at the end I'm seeing 15.7 mpg! If the road was longer maybe I would seee more, but then after that it's all short stop and go, your basic city driving after doing that for a month I average out around 7.1-8.0 mpg because it's not getting any highway use! I'm going to take off the CAI for a month and see what happens.

So nobody thinks a plug change will make a difference?

Also the best I've ever seen was 16.5 mpg and that was driving through the rockies! But I also had roof rack overhead storage bin,a loaded hitch hauler, for a total of 1000lbs etc luggage. I'm sure that had an effect on mpg's!!

 

A plug change may make some difference. The overhead calculator isn't terribly accurate. Calculate your mileage by hand for a few times and see what your mileage actually is.

 

To those of you who don't care for my characterization of my 03 Ex 4.6 as "undrivable" I would ask if any of you have used a custom tune, or know why they make them?

The stock configuration of the Expedition is trying to reach the "average" consumer, most of whom are probably ladies, hence the need to add a button that moves my gas and brake pedals in and out. Most average size men don't need that. I have read similar observations on other boards, so this is not just me.

The fact is, these trucks have the capability of running much better than they are set at the factory. They can shift better, develop more torque for pulling (itself and cargo or boats or whatever), develop more horsepower etc.

And lest you think I'm just trying to hot rod my Ex, I will share with you my wife's observation that the truck in stock configuration is almost dangerous with respect to needed emergency manuevers i.e., passing or avoiding things at highway speeds. SHE likes the performance tune because it gives her greater control over the vehicle via acceleration, torque and power.

The moral of the story is, don't knock it if you haven't tried it.

If you want a good forum for investigating tuners, go here:

http://www.f150online.com/forums/forumdisplay.php?f=34

 

Passing and swerving are hardly "emergency moves" I would consider stopping a better one. But then we'd go into tires and rotors and good god another can of worms...LOL

 

I get a rock solid 11.5 mpg in town. I installed a K&N filter and a cat back Magnaflow exhaust; zero change in mpg, but 100% increase in noise. Magnaflow was removed and then after I heard a few stories of oil from K&N's taking out mas-flow air sensors, the filter joined the exhaust system. The electric fan is the only thing that I am sold on for actually improving mpg (although I have not made that mod yet).

 

They don't take out the MAF so much as just get oil on it. A little bit of electric contact cleaner or brake cleaner takes care of that.

I will vouch for the e-fans improving mileage. I put one in my Explorer and it definitely helped with throttle response and I picked up 2 or 3 mpg depending on the day. I actually nailed 25mpg in that truck on the interstate.