05' getting 40mpg if I'm lucky

....hmmm....my profile pretty much matches recyleman's, new-to-me '05 with 40K miles on it.
I drive 106 miles of freeway/desert highway a day.
Average per the computer is 41-42mpg any given day.
Had my first fill up today, 10.2 gallons but that's 37+ mpg...
I'll be dammed if I'll drive in this heat without AC.

One thing I do know is that the oil is overfull about 1/4"-1/2" on the dipstick.
So...what does overfill do to the mileage?

 

1) Have you reset the avg mpg computer after buying it?

2) 10.2 gallons in does not mean 10.2 gallons used in a GenII. You have a bladder, not a fuel tank. You will never get the same amount in as out, so you cannot do tank to tank calculations like any other car. Rely on the MFD or average over tens of tanks at a minimum.

3) At highway speeds, AC is more efficient anyways. But try to keep it out of the excessive range. Don't expect to cool the cabin to 15 when it is 40 outside and not take a mpg hit.

4) Oil overfill destroys mileage.

5) Also check your tire pressure, and what type of tires. Since you are not the original owner, the previous owner or even the dealer may have replaced them with non LRR tires.

 

I reset the average at each fillup. (Drove to Vegas and back and averaged 43mpg)..

AC at max until I get comfy, usual 2-3 miles, then turn the fan down to M andhave the temp set at 72.

I have new OEM Goodyear touring tires set at the recommended pressure per the owners manual.

I've read many quotes mentioning the oil overfill thing, but I haven't read exactly why....

 

Depending on the outside temperature 72 degrees may be too low.

I performed a series of tests today and even though outside temp was only 90 degrees, I could not avoid the 10mpg hit no matte what I did. Even after driving 50 miles with the AC cranked on full blast the cabin would simply not cool down to 70 degrees or lower.

Try turning off the AC and watch your instantaneous mpg indicator shoot up. You need to be on a level road and keep a steady speed.
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Double check your tires and report back the exact name of them. And the recommended in the manual is low. If you want a cushy ride, then sure. But don't expect 50mpg or anything close at 32psi.

 

Try running for the first minute or two with the windows down, then with the AC on recirculate at about 75 after that.

It can slosh against the crankshaft and increase friction.

 

That is why you are not getting 50+mpg.

 

P185/65R-15 Goodyear Assurance ComforTred Touring
I believe the recommended PSI in the owners maual is somwhere in the 40s which is pretty normal for a mid-size sedan. Only non-standard thing is the recommended PSI is different front and rear. Something like 40/42.

I sucked a full 1/2 quart of overfill out of the motor last night. Boy look at the mileage shoot up! NOT.

I tried turning the air off for a couple miles, really saw no appreciable difference at all. So far I've read on this forum two completely conflicting sets of 'facts' about the AC versus mileage.
S'o.k., pretty typical frum stuff.

As far as measuring your fuel consumption by calculating at the pump, well, if you can't trust the computer, and you can't trust the pump, then just how do you calc mileage? Sounds pretty vague.
378 miles on 10.2 gallons figures out to 37.6mpg the way I see it.
No two ways about it.

 

No, it is 35/33.

You did not perform the test properly. If you had the AC running prior to your "test" then the cabin was likely already cooled down and the AC did not need to run hard. We've stated many times that it is the initial cool down process that kills MPG and that if the ambient temp is close to your AC temp setting then the mpg hit is very small. Try doing a bit more research on this subject before you roll your eyes.

You apparently were not listening to those who tried to explain the bladder-based fuel tank. It does not always hold the same amount of fuel. If it expands and holds more fuel than your last fill up then your hand calculated mpg will be off. Therefore it is imperative that you perform hand calculations over a large number of tanks to calculate your actual average mpg. Since this has been done by many members over the last 7 years we know that the average mpg discrepancy between the car's calculations and hand calculations is approx. 2%.

 

recycleman,

Are you still observing the low battery bars when you do not run the AC and you are on the freeway? In the GenII, the battery likes to be at about 64.5% SOC. So when traveling for more than 15 miles the car should be at 60-65% SOC unless you are under high load like going up a hill. I don't remember how many bars that equates to but I'll check today.

If possible do you think you can spring for a ScangaugeII? It would help you diagnose the car by checking other parameters like SOC %, Codes, battery temperature etc.

 

I highly doubt your HV battery is on the way out. It is very hot where you are, the battery is running hot (the fan comes on loudly). In "loud mode" you are basically driving a Yaris with a couple hundred extra pounds in the back. Easiest way to test your HV battery:

Turn on your AC/lights/whatever to drop your HV state of charge to 2 bars. Turn off the electric drains. Accelerate to 50mph, then brake lightly so you are only using regen and come to a stop. How many bars do you have when you come to a stop.

You said in the other thread you have the OEM tires. Please double check and post what exactly they are. LRR tires make you take a hit. (3-5mpg on average, more so for some).

The AC always has an effect on mileage, you just may not have seen it last year.

 

I don't think many freeway-centric drivers will keep the car happy at 64.5%. All the interstate I have driven has been roughly the same. When you follow in a pack, you fluctuate speeds by about +/- 10mph at least. Usually the lead car realizes it has slowed down, then guns it. Everyone else follows, and eventually the speed bleeds off or you are forced to brake, then accelerate hard back up to speed. This means the SOC will be low the entire time.

Stick it on cruise control at 65mph on level ground and it should find its way to median SOC happily.

 

The battery bars will not usually go all the way to the top unless you are driving down a nice hill and can regen a lot of power. Otherwise the bars are usually about 2-3 from the top if you are casually cruising on the freeway. That is pretty close the the 64.5% I was talking about.

Your traffic must be different than the stuff I drive in around here. We have anywhere from 3-6 lanes of freeway so it's easy for me to just tool along at 65mph in the slow lane. The number I constantly observe is that 64.5% unless like you said, I have to gun it to pass or keep from annoying other drivers. Then it may drop into the mid-high 50s for a bit. Cruising on the back roads I drop down to 50-55mph and the SOC just sits between 60%-65%.

 

I hear ya. Testing the AC thing in hot temperatures sucks. I find that if it is really hot during my testing I can open my driver's side window about half way and crack the rear passenger side window about 3" and it creates enough airflow through the car to keep me relatively cool. In 115deg heat you're basically screwed. Or should I say cooked?

Seriously, if you have the money invest in a Scanguage. If you were closer I'd let you borrow mine.

 

Then relax, your HV battery is perfectly fine.

At this point, I would say the only thing related to the HV pack is temperature. Reading the CAN bus you can get the temperature of the cells. Listening for the fan, you can get an idea of the temperature. If the fan is not audible, then either a) the pack isn't hot or b) it is hot, but the fan/fan control isn't working correctly.

Do you have an electrical degree of somekind? The high voltage DC of the battery pack can kill. You will be hard pressed to find anyone encouraging someone of little electrical knowledge to poke around back there.

 

Yikes! That is not good.