RC F (2015-present) Discussion topics related to the RC F model

How Low Can You Go

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Old 05-24-17, 01:21 PM
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WolfManRCF
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Default How Low Can You Go

Been looking at my fuel consumption lately and the reading I'm getting from the onboard computer is approx 13.7 mpg? Couple of possibilites:

1) I drive like an animal.

Really, I don't think I drive like an animal. I drive in a spirited fashion, sport manual 60% to 80% of the time, sport + manual 20%, occasional automatic in sport mode.

2) There is something wrong with the engine in my car.

Is it possible one of my injectors is stuck open?

Anyone else dipping into the 13 mpg tank after tank? I only use premium 91 gas. My car is at approx 19,000 km or 11,800 miles and is my daily commuter.

Also I'm experiencing significant engine oil consumption. Currently I'm seeing the following consumption:

0.8 L per 1000 km or
0.84 q per 621 mi

Also currently undergoing engine oil consumption tests with a Lexus dealer to investigate this problem.

wolfman
Old 05-24-17, 02:02 PM
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Sparker
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I get the same avg mileage during everyday driving conditions since it mostly consists of local areas with stop/go. I frequently make 200mile roadtrips where I avg 22-25 depending on traffic situation. It's more so about how low and to keep the revs which is through consistent speed/gear. On the highway, the engine is humming along smoothly at 2k rpm around 80mph which will yield much better mpg results then stop/go at 30-40mph.
Old 05-24-17, 02:14 PM
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MDElliott
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I fluctuate between 16.9 - 17.1 and it has never been higher than 17.1. Currently have 3,200 miles and I drive normal 90% of the time.
Old 05-25-17, 11:56 AM
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shadow1118
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i get that same if i drive like an f1 driver , like flooring it multiple times.
Old 05-25-17, 12:36 PM
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paulwall4
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I've gotten as low as 12
Old 05-25-17, 03:25 PM
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Dsully
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The lowest i've gone is in the 15's, and that was mostly in stop and go city driving with maybe 20% freeway. My absolute best was 32.5 mpg over 200 miles cruising on the freeway with cruise control on, while in eco mode! I think you are in the's 13's mostly because you are in manual mode. The car doesn't shift down up to a higher gear at low RPMs which means you are burning more gas due to higher RPMs. As for the reason, I suspect it is because of the torque converter lockup that happens in sport and sport+ modes once you pass 2k RPM?
Old 05-26-17, 08:38 AM
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Basically if you are in 2nd gear, and your torque converter has already locked up (I think around 2.2k or so) it won't let you manually shift to third until a certain rpm limit the ensure that it stays locked up. In normal driving the car shifts as fast as possible, keeping the RPMs low, but in manual mode with sport and sport plus, it doesn't let you drop the RPMs below the threshold for the lockup in the lower gears. I am no expert in this, however that is the only explanation I have, and I could very well be wrong as to why it doesn't let you do that.
Old 05-26-17, 10:46 AM
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Deanrcf
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I believe sport and sport plus also have the most aggressive Ecu mapping, which advances timing and adjusts afr . Regardless of manual mode or auto, these modes will inherently use more fuel. You can't advance timing safety without fuel.
Old 05-30-17, 03:22 PM
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yooniverse
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Originally Posted by WolfManRCF
Been looking at my fuel consumption lately and the reading I'm getting from the onboard computer is approx 13.7 mpg? Couple of possibilites:

1) I drive like an animal.

Really, I don't think I drive like an animal. I drive in a spirited fashion, sport manual 60% to 80% of the time, sport + manual 20%, occasional automatic in sport mode.

2) There is something wrong with the engine in my car.

Is it possible one of my injectors is stuck open?

Anyone else dipping into the 13 mpg tank after tank? I only use premium 91 gas. My car is at approx 19,000 km or 11,800 miles and is my daily commuter.

Also I'm experiencing significant engine oil consumption. Currently I'm seeing the following consumption:

0.8 L per 1000 km or
0.84 q per 621 mi

Also currently undergoing engine oil consumption tests with a Lexus dealer to investigate this problem.

wolfman
Drive it like an animal. Isn't that why we bought this car. At least for me I do... I've never looked at how many miles I get per gallon. I just drive it hard.
Old 09-18-17, 09:10 PM
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lexusrus
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I'll need new tires soon. LOL 😄😄😄😄😄😄😄


Originally Posted by yooniverse
Drive it like an animal. Isn't that why we bought this car. At least for me I do... I've never looked at how many miles I get per gallon. I just drive it hard.
Old 09-19-17, 08:54 AM
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JB5674
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Try seafoam for BG MOA in your gas tank. This should help with the injector issue. I'd reset your ecu, just remove the negative battery terminal over night then reinstall. See if the same exists. Likewise, if you don't have the TSB for the fuel pump, get it. It's an enhancement of the stock tune.

Good luck
-JB
Old 09-20-17, 10:58 PM
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lobuxracer
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Originally Posted by WolfManRCF
...Also I'm experiencing significant engine oil consumption. Currently I'm seeing the following consumption:

0.8 L per 1000 km or
0.84 q per 621 mi

Also currently undergoing engine oil consumption tests with a Lexus dealer to investigate this problem.

wolfman
Sounds like the engine was babied too much on break-in and the rings aren't sealing for crap. Poor fuel efficiency and high oil consumption are commonly from rings that never got broken in fully.
Old 09-21-17, 11:07 AM
  #13  
Apone
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that mpg does seem very low compared to what I get. I drive in Sport usually as throttle response in normal is unbearable. Try driving along and using the paddles while in full automatic. The car will do what you ask and then in very short order, start racing back to 8th gear, even if you are still playing around. Now, if you move the stick over to full manual, you will hold those gears a lot longer. The auto is programmed to race to the top and save gas, your brain is not. I suspect you know all of this though. Your results seem unusually low as even in full maniac mode I can't get it that bad.
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