23 mpg??

[Matsuda03]

I just bought the car. It's an 03 "manumatic" with 64K miles. A great car!

I calculated my mileage on a short 150 mph road trip yesterday- 23 miles per gallon. Is this normal?

My method for determining the mileage was:

Fill the tank. Reset the trip meter. Drive. Fill the tank.
Divide miles on trip meter by gallons required to fill the tank.

The last owner gave the car its 60k service- so it should be well tuned...

Any suggestions?

 

[Tom03es]

How fast did you drive during those 150K miles? I also have the "manumatic"/triptronic/sport shift or which ever of the dozen or so names this transmission has. Most of my "in town" tanks yeild about 25-27 mpgs with a good mix of city and highway. I've seen tank averages as low as 22 while draining a tankful on the interstate around 85 mph. And I've seen tank averages as high as 33 with easy cruising at 65-70 mph. This car with that transmission seems to be very sensitive to how you drive it.

 

[RABID_MP5]

What was the ambient temp like too? I know I'm off a good 10 percent since the last month with temps in the 30s. It idles faster longer, but even on a 250 mile trip from full it used more. Winter grade gas? Cold air intake (I keep thinking of the inlet air temp sensor next to the MAF sensor - especially since I have a CAI into the fender well) Thermostat? (temp gauge reads normal) I did air up my tires to compensate for their seasonal pressure drop. 10W30 oil.
Also, yeahs autos are dinged routinely on here for their mileage. And I have never had a car with more potential for inconsistent fillups - typically a full gallon can be added after the pump first clicks off - so you need to log over several tanks to get a good idea.

 

[Sveivo]

I just bought the car. It's an 03 "manumatic" with 64K miles. A great car!

I calculated my mileage on a short 150 mph road trip yesterday- 23 miles per gallon. Is this normal?

My method for determining the mileage was:

Fill the tank. Reset the trip meter. Drive. Fill the tank.
Divide miles on trip meter by gallons required to fill the tank.

The last owner gave the car its 60k service- so it should be well tuned...

Any suggestions?

My suggestion is to slow down?? 150 mph is way to fast for this car. I'm curious how you even got it to 150? Most people have gone 140 mph or so, and that is sometimes hard to achieve.

 

[MixinMP5]

yeh dude...150 will not get you good mileage haha

 

[LASERBLUE135]

I might suggest that the milage was a fluke, try the test over a longer range of miles. You should get high 20's at least.

 

[rooster1]

23 mpg is pretty good for a short 150mph trip lol

 

[Matsuda03]

Oh, I can't believe I wrote 150 mph instead of 150 miles. It could be done... all mods, downhill, tail wind...

I have another, longer trip planned. I'll calculate my average after more tanks.

 

[icontender]

in the summer I was consistently seeing 28mpg. That is in atlanta with good city/highway mix. I also drive in the 4k range and not much higher. However, since its been colder the mpg has really suck. I think I am at 24mpg or so now.

Also,

I only have the K&N filter installed.

 

[i12drivemyMP5]

I pretty much get 25 mpg all year long regardless of AC or not, freeway or not.

 

[THE Phen]

Yours isn't the first auto car that I've heard getting sub-par mileage. What speed were you going? Anything over 70 and mileage falls off pace FAST.

 

[JAmdownPR5]

well i must be the worst of them all I will get 19 - 23MPG... 23 on a good HWY trip

 

[jazzman]

WOT and MPG just don't go well together. lol

 

[Sveivo]

well i must be the worst of them all I will get 19 - 23MPG... 23 on a good HWY trip

Well, that's about the same as the Escalade Hybrid. (boom03) So think about what you could be driving (wink)

WOT and MPG just don't go well together. lol

Actually WOT != bad MPG for me. Running at high RPM constantly is not a good idea, but WOT in and of itself is not bad. I actually think it's required for good MPG (in moderation).

But there are different schools of thought regarding this.

 

[jazzman]

Running at high RPM constantly is not a good idea, but WOT in and of itself is not bad. I actually think it's required for good MPG (in moderation).

But there are different schools of thought regarding this.

Explain?

 

[808MP5]

I get about 22 but I'm boosted

You should get high 20's depending how you drive. If on long trips set cruise control at 60mph you'll get great mileage

 

[Sveivo]

Explain?

Basically accelerating quickly to get into a fuel efficient gear (like 5th gear) is not inherently bad.

 

[THE Phen]

You can kinda think of the throttle body as a restriction that is hurting mileage. Freer air flow = more efficient engine. But of course, this doesn't mean that you can stand on it all the way to redline in all 5 gears.

 

[Flash5]

5-speed ftw! but depending where you live you might be using winter gas now which is known to give lower mileage, I know here thats what we are using now and my milieage is around 25-26 city/highway mix. in the summer i get closer to 30 but with gas prices at 1.99 here i really am not complaining about what i am getting, i mean seriously, 5 gallons for $10! its like we are stealing it!

 

[THE Phen]

Yeah, I noticed that you guys over in Lehigh Valley were paying a lot more than I am for gas when I was there a few weeks ago. Heh.

Winter blend gas, 5 speed, and me on my fill up last night netted 28.4 mpg. That was with one day of stand still traffic, and warming my car up for 10 minutes in the morning.