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Discussion Starter #1
Just finished my break-in period (thank God), and made the following observations:

Following break-in requirements, I kept my speed under 65 mph. Also noticed that the RPMs were at about 1500. Fuel economy was at 25 mpg, as advertised.

After the break-in was over, I noticed that at speeds above 65 mph that the cruising RPMs were at 2000 and above, and that my fuel economy was much less (at least according to the fuel economy meter) at around 20 mpg.

My question is: As I drive the car more, will the cruising RPM decrease? Is there anyway to reduce cruising RPMs levels? I'm pretty certain that this is the reason why my fuel economy is decreasing (although, as a newb, I could be wrong).

And yes, I already know that the best fuel economy for pretty much any car is at around 45-55 mph. According to many posters, over time and miles, the fuel economy increases. Just wondering if this has anything to do with it.
 

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"As I drive the car more, will the cruising RPM decrease? Is there anyway to reduce cruising RPMs levels? I'm pretty certain that this is the reason why my fuel economy is decreasing (although, as a newb, I could be wrong)."

No the RPMs will not drop.
The RPMs are a direct result of the "gear ratio" which is a bit of a misnomer here. It will take awhile tho before we accept "Spool ratio".;)

The ratio os computer controlled and is part of the profile associated with D function.
But you still may get better MPG when you get 5-10K miles than you are getting now. There is still a good bit of stiction to overcome and that will wear down gradually.

2000 RPMS tells me that you are criuisng at about 75MPH.
You won't get sterling mileage at that speed. (Same Cruising speed I use on Interstates BTW). I am currently getting 20MPG at 75 MPH and I too just passed 1500 Miles.
I am not expecting anymore than 21 when the car is fully broken in.

BTW, I used Ds quite a bit when I was breaking it in (with a steady throttle however) and therefore, my Mo has seen widely varying RPMs during break in with perhaps 5-10% of the time at 3-4000 RPMs.

Homer
 

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Discussion Starter #3
Thanks for your reply. Because most of my highway travelling will be above 70 mph, I was hoping to get better mileage. Oh well.
 

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I track my milleage very closely (with each fill up and in a PC, I used to graph it but stopped for obvious reasons :p )

I average 75-80 MPH on the highway when traffic permits however my average speed according to the MO is only 38 MPH. I'm am getting just about 20 MPG. At some point I hope to take a long HW trip and see how much I can get out of the MO at 65 MPH.
 

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So, at 65 MPH, your RPMs are still at 1500? and RPMs increase if you go faster? Sounds like you're stuck with it. The engine/CVT controls are deciding you need more power to go faster.

If the RPMs at 65 MPH suddenly changed, that's a whole different story... that would indicate a TCC failure.
 

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What was I thinking? Please ignore the mindless post above this one.

In any highway cruising situation, the CVT will be in lowest (numeric) ratio, for optimum mileage, with TCC engaged. Engine RPM will vary in direct proportion to road speed.

If you have observed a sudden shift of RPM at a given road speed, then you should take it in and have the TCC checked.
 

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turbodog said:
What was I thinking? Please ignore the mindless post above this one.

In any highway cruising situation, the CVT will be in lowest (numeric) ratio, for optimum mileage, with TCC engaged. Engine RPM will vary in direct proportion to road speed.

If you have observed a sudden shift of RPM at a given road speed, then you should take it in and have the TCC checked.
Without the throttle position changing too. i.e. on level ground, constant speed, constant throttle position, auto in steady state. Then the RPMs should not change.
 

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Took our MO to West Va Thursday. The Interstate crosses several mountains. Had cruise control on 75 mph. It was interesting to watch the gages as we went up and down the steepest grades. The rpms stayed in a range of 2000 to 3000. The mpg rose and fell between 16.8 and 21.3. So the fuel economy wasn't great -- it WAS great to pass the many vehicles who weren't able to take steep grades at 75 mph. :cool:
 
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