MPG problem

[morrises]

We took a trip back to Indiana last weekend and were getting around 19 mpg for the whole trip. The tires were perfectly inflated. I'm wondering if something isn't right with how the cold air intake was installed or if the computer needs reset. I know the plugs and wires had been replaced before we bought it, but maybe they put in the wrong ones. We were highway the whole trip.

Any thoughts?

Jeremy

[CREWZIN]

Jeremy.

I could be a number of things but before going over all of them how bout reading all 3 pages of the discussion on MPG on this thread. Might give you some ideas.

MPG does not suck

[Hooligan]

Originally Posted by morrises

We took a trip back to Indiana last weekend and were getting around 19 mpg for the whole trip. The tires were perfectly inflated. I'm wondering if something isn't right with how the cold air intake was installed or if the computer needs reset. I know the plugs and wires had been replaced before we bought it, but maybe they put in the wrong ones. We were highway the whole trip.

Any thoughts?

Jeremy

Jeremy, if it is a AirAid there is only one way it can go on. I just bought a 2008 NA and have already changed plugs & wires when I got it (approx. 200 miles), I also installed my AirAid intake and the last fill up (both city and highway we got 19 with only 700+ miles on it.

But like Crewzin said check the link before you start "plunging" into fixing something.

[morrises]

It also has a trailer hitch, but i think it's aftermarket. So I don't think that it came with a towing package transmission. I'll read the other post.

[soonercruiser]

Yes..any number of things!
1. Did you say "computer" reset? Don't trust the mpg reading on the dash!! Actual/accurate MPG readings are done by filling up the tank, noting the mileage and doing your own calculations, as you refill each time.
2. Even the mpg calculations can be off if you have an other than OEM rim & tire size. That's why most of the posters on the PT sites are mentioning using a tire size calculator in selecting tire sizes to be as close to OEM as possible.
-other wise you will have to bring the tire size conversion factor into play in your calculations too. (e.g., a smaller size tire would turn more per unit of road, giving you the sense that you were travelling farther on a tank of gas....when actually you are travelling a shorter distance)
...the DML Tire Size Calculator link below is one that some of us use in choosing new tires...
DML Tire and Wheel Calculator

[digitalpinscruiser]

Originally Posted by soonercruiser

Yes..any number of things!
1. Did you say "computer" reset? Don't trust the mpg reading on the dash!! Actual/accurate MPG readings are done by filling up the tank, noting the mileage and doing your own calculations, as you refill each time.

Yep I dont trust the computer on the dash. I am going to reset mine this weekend, before me their was one owner to my PT whom put 20,000 miles on it. My computer on the dash is telling me that I am getting 12.2 mpg which I know is not right at all. I have had my PT for about a month and a half now. So I am definently going to reset the computer. I just know that its wrong, also I was a quarter away from filling up the tank last weekend and I watched the computer. The mile to empty kept jumping up and down, this was happening 30 minutes after I filled it up.

[Hooligan]

Forget the dash MPG readout. I use mine to regulate how I drive, IF I can keep it between 17.9 & 18.2 city driving I'm a happy camper. Less than that I know my fill up mileage will suck.

What we mean by resetting the computer is removing the negative cable for 5 /10 minutes, that resets the engine computer, NOT the dash MPG readout.

[ptborder]

having a base model(even my GT didn't have the readout), I was'nt aware some on here were using it. Geez, the Ford Excursion(V 10)I drove for awhile used to register up to 18mpg at times. But it never broke 11mpg.
It's important also to:
1. always fill up at the same approximate time of day...ie; morning or early evening.
2. determine if you are going to stop at the first click, second or when it spills onto your brand new $100 shoes.
3. reset the trip odo or write the mileage down right then, not later because you'll remember it. You won't.
Use the calc in your cell phone to figure it before you drive out of the station. Safer than doing it at 80 in traffic.
4. Don't change more than one thing at a time if you really want to determine what is improving or harming your mileage.

[ucantcme]

How fast were you going the whole way? Cruising at 70 and going 80 are going to make a HUGE difference.