Cruise control and fuel consumption

[Fazda]

It all depends on the average weight of the driver's foot...

It is not difficult to drive economically and to maintain a steady speed without CC, but many people find that too difficult.

I use mine when I am tired or am in an area where speed limit is too low for the road situation, like the section from Mooi River to Howick where it is downhill, the road is beautiful and the bastards have a 100 km/h speed limit...and have a trap every couple of k's! There it is far less stressful to set it at 100 and let the CC do the work. It is unlikely to save fuel simply because it cannot anticipate road conditions, as has been said before...but having said that, the more time I spend on the road, the more drivers I find who haven't a clue what is going on on the road!

@powermzii - I would be most surprised if your car didn't make it to PE on one tank...it would have to be doing worse than 8.8l/100, and most modern cars can beat that figure on a long run unless you drive like a total tosser...

 

[JK8]

It makes a difference with Turbo cars or High performance cars, CC can save you petrol even with slight inclines.
Ive noticed on hills in JHB my fuel consumption goes up from 3l to 4l when climbing a hill but on the downhill it drops to 0l!

But then I tried driving at 160 and then just roll (in gear) I can cover greater distances using 0l!! Eg Midrand toward Allandale through to Buccluegh interchange from 160 freewheeling I can maintain a speed above 120 till Woodmead.

I was bored, fuel consumption worries are for losers!!

 

[powermzii]

It all depends on the average weight of the driver's foot...

@powermzii - I would be most surprised if your car didn't make it to PE on one tank...it would have to be doing worse than 8.8l/100, and most modern cars can beat that figure on a long run unless you drive like a total tosser...

will let you know - 3 weeks to the trip and i guess the proof is in the driving . I DID drive from JHB to CTN at the end of last year and used 2.5 tanks - still had about 1/3rd of a tank when i arrived here

 

[Kbeat]

To be honest I never use a cruise control. I dont even know if it functions on both my cars.

 

[Pointing1]

Thought i would add my experience to this - over a 640km round trip...320km no cruise control average speed around 130km/hr fuel consumption average 7.8l/100km. 320km return cruise control at 140km/hr fuel consumption average 8.3l/100km

 

[MFour]

hmm now can you do both journeys again at the same speed please

 

[koeks]

 

[powermzii]

so i finally drove to PE and back over the weekend, Consumption avergae on the way there was 7.0lts/100kms without cruise control at about 100kms/hr. On the way back increased speed to 120 and invoked cruise control and the figures went up to 7.5lts/100kms - granted there were times when i was caning it

 

[MFour]

so i finally drove to PE and back over the weekend, Consumption avergae on the way there was 7.0lts/100kms without cruise control at about 100kms/hr. On the way back increased speed to 120 and invoked cruise control and the figures went up to 7.5lts/100kms - granted there were times when i was caning it

That's pretty good, if taking the speed increase into consideration then it would appear that CC has given you a bit of a saving.

 

[HavocXphere]

But then I tried driving at 160 and then just roll (in gear) I can cover greater distances using 0l!!

Unless you are switching off the motor you are not doing 0l.

 

[sonxEr77]

I used it once when i wanted to sleep ... awesome ...

 

[ALFAHOLIC]

I went on a trip to Cape Town two weekends ago...i used the cruise control at a speed of 130kph and timed it optimally - meaning, at the optimal rev limit and speed...you should be cruising at the optimal! With my foot pressed as softly as possible on the gas pedal, I averaged 8.5l/100km at a speed of 130kph in a 20 16v with the revs at 3500rpm. But with the cruise control on...I timed it at 130kph and the revlimiter at 3500rpm....I set it there...and it yielded 8.4l/100km....anyone who drove from JHB to CT knows that its a long @ss trip, so you ge tto experiment a bit. What I did was floor the car to about 150kph...then leave the gas pedal altogether so that the car can gradually slow down to 130kph...with no set revs...I stopped the revs at about 3450rpm at the speed at 130kph and it yielded at the maximum a 8.4l/100km and at the minimum a 6.9l/100km...that was amazing. From CT to KBY the car used 1 and a half tank of petrol where it used to use 2 tanks tops...my avg went down from 8.5l/100km to a lowely 7.5l/100kms...damn! CRUISE CONTROL FTW!

 

[Ou grote]

I went on a trip to Cape Town two weekends ago...i used the cruise control at a speed of 130kph and timed it optimally - meaning, at the optimal rev limit and speed...you should be cruising at the optimal! With my foot pressed as softly as possible on the gas pedal, I averaged 8.5l/100km at a speed of 130kph in a 20 16v with the revs at 3500rpm. But with the cruise control on...I timed it at 130kph and the revlimiter at 3500rpm....I set it there...and it yielded 8.4l/100km....anyone who drove from JHB to CT knows that its a long @ss trip, so you ge tto experiment a bit. What I did was floor the car to about 150kph...then leave the gas pedal altogether so that the car can gradually slow down to 130kph...with no set revs...I stopped the revs at about 3450rpm at the speed at 130kph and it yielded at the maximum a 8.4l/100km and at the minimum a 6.9l/100km...that was amazing. From CT to KBY the car used 1 and a half tank of petrol where it used to use 2 tanks tops...my avg went down from 8.5l/100km to a lowely 7.5l/100kms...damn! CRUISE CONTROL FTW!

That sounds like pretty responsible driving for you.

 

[ALFAHOLIC]

That sounds like pretty responsible driving for you.

Ja...I know, I kind of grew up the last couple of months, arn't you heppie?

 

[Claymore]

That sounds like pretty responsible driving for you.

Oh, could you figure out what it meant?

 

[J25]

I went on a trip to Cape Town two weekends ago...i used the cruise control at a speed of 130kph and timed it optimally - meaning, at the optimal rev limit and speed...you should be cruising at the optimal! With my foot pressed as softly as possible on the gas pedal, I averaged 8.5l/100km at a speed of 130kph in a 20 16v with the revs at 3500rpm. But with the cruise control on...I timed it at 130kph and the revlimiter at 3500rpm....I set it there...and it yielded 8.4l/100km....anyone who drove from JHB to CT knows that its a long @ss trip, so you ge tto experiment a bit. What I did was floor the car to about 150kph...then leave the gas pedal altogether so that the car can gradually slow down to 130kph...with no set revs...I stopped the revs at about 3450rpm at the speed at 130kph and it yielded at the maximum a 8.4l/100km and at the minimum a 6.9l/100km...that was amazing. From CT to KBY the car used 1 and a half tank of petrol where it used to use 2 tanks tops...my avg went down from 8.5l/100km to a lowely 7.5l/100kms...damn! CRUISE CONTROL FTW!

I'm a complete car noob, so excuse my ignorance, but isn't the speed dependent on the selected gear and the revs? How can you independently set the speed and the revs? Do you have a continuous gear box? Maybe I'm just misunderstanding your post. Also, are there cruise controllers in which you can set the desired revs, as opposed to the desired speed?

 

[ALFAHOLIC]

I'm a complete car noob, so excuse my ignorance, but isn't the speed dependent on the selected gear and the revs? How can you independently set the speed and the revs? Do you have a continuous gear box? Maybe I'm just misunderstanding your post. Also, are there cruise controllers in which you can set the desired revs, as opposed to the desired speed?

Hi, no, no funny gearbox...it all depends...look, for my car, a 2.0 when I hit 3500rpm I'll be at 120kph in 5th gear...but like I said, I pushed to 150kph, and let the revs drop and set the revs at about 3450 to 3500 so not to strain to engine but still maintain that speed...try it in your car...never set the cruise control when you are still accelerating, accelerate to above your set speed, so if you want to be at 120kph, accelerate to about 140 and check the revs...set it at rev speed and cruise on...it will consume less, well at least in my car.

 

[JK8]

Unless you are switching off the motor you are not doing 0l.

It idles at 0.6l per 100km, when rolling it shows 0.0l.

 

[Naks]

It idles at 0.6l per 100km, when rolling it shows 0.0l.

Indeed, modern engines (petrol & diesel), do not use any fuel when coasting in gear! I also did not believe this at first, but s'true

On my A3 TDi, the cruise control returns better consumption, whether it's driving to work in traffic or long distance. As soon as I see some open road, I hit the CC and let the car do its thing. When I see a red robot from a distance, I cancel the CC and coast until the white line and then only do I stop - this means the last 100-50m or so is diesel-free. Ditto on long downhills.