Cruise Control and Fuel Consumption - Thinline
Hello

I am sure someones knows the answer to this?

Does using cruise control use more fuel than using your foot?

Cheers
Cruise Control and Fuel Consumption - Falkirk Bairn
It is regarded as less fuel consumption - the car keeps a constant speed and is not subject to speeding up/down as your foot moves slightly on the accelerator.
Cruise Control and Fuel Consumption - tr7v8
My Renault 25 V6 used to do 10% improvement with CC being used & on a run that meant 30-32MPG. Damn good for a big V6 auto in a big mobile lounge! Shame the rest of it was so pants.


Cruise Control and Fuel Consumption - Andrew-T
Probably good on the M-way if you don't set a stupidly high speed. I would think rather uneconomical on hilly roads if the car tries to maintain an impossibly high speed.
Cruise Control and Fuel Consumption - Altea Ego
Its regarded as HIGHER fuel consumption. Its far more brutal than an average right foot
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TourVanMan TM < Ex RF >
Cruise Control and Fuel Consumption - tr7v8
Owned 2 cars with cruise R25 V6 as above & Mondeo Ghia X 2L.
Both had very smooth cruise control, hence better fuel economy, my late ex-MiL could tell the difference cruise on or off. Also doesn't get bored or relax the right foot after an hour or so.
Cruise Control and Fuel Consumption - Bill Payer
You could in theory do better, by easing the car up hills, and allowing it to build up speed down hills. Also, with cruise on, if someone cuts in front of you you've usually got to brake more sharply - if not using cruise you may well have backed off earlier.

The problem in practice is that it's impossible to maintain the above practices consistently for long periods.
Cruise Control and Fuel Consumption - cheddar
Its regarded as HIGHER fuel consumption. Its far more brutal than
an average right foot



The cruise control on my Mondeo is so subtle on take up, much more so than my right foot. I drove a 607 with cruise, now that had a brutal take up.
Cruise Control and Fuel Consumption - Roly93
Probably good on the M-way if you don't set a stupidly
high speed. I would think rather uneconomical on hilly roads if
the car tries to maintain an impossibly high speed.

>>
Agree with the above, and in general, patient use of the throttle even on the motorway usually beats the use of CC every time, although I admit to just sticking the CC on and cruising myself. If you saw Clarksons economy run film on Top Gear, in the Audi A8 V8 diesel this was bourne out there.
Cruise Control and Fuel Consumption - Roger Jones
Having used cruise control in many hire cars in North America and in an Audi 100, two MB Coupés, one MB S-Class and an MB W124 300E, frequent use of cruise control has consistently reduced fuel consumption. I'm not surprised, because its response is far more sensitive and rapid than that of my right foot.
Cruise Control and Fuel Consumption - Roger Jones
www.edmunds.com/reviews/list/top10/103164/article....l
Use Cruise Control Selectively
Using cruise control can improve your gas mileage by helping you maintain a steady speed, but only if you are driving on mostly flat roads. If you are driving in hilly terrain, using cruise control typically causes your vehicle to speed up faster (to maintain the preset speed) than it would if you were operating the accelerator yourself. Before you push that cruise control button, think about the terrain ahead.

budgettravel.about.com/od/cheapgroundtransportatio...m
Use Cruise Control
It's the old "Tortoise and Hare" story: Steady wins the economy race, too. If you use cruise control on the highway, you've no doubt observed many people do not. That's because you see them speed past you one minute, and then you must pass them a few minutes later. Maintaining a constant speed is pleasing to your engine. One exception: Don't use cruise control on wet roads, where it increases the risk of accidents.

www.whatprice.co.uk/car/fuel-saving.html
Use cruise control to maintain a steady pace on the highway to increase fuel economy.

www.ford.com/en/goodWorks/environment/airAndClimat...m
From Top 10 Eco-Driving Tips
On the highway, use cruise control whenever possible.
Cruise Control and Fuel Consumption - none
One of our office ladies has a Passat diesel auto with cruise control. When she uses it, she finds it very disconcerting to have the gearbox changing up and down unexpectedly.
Cruise Control and Fuel Consumption - robcars
Cruise control is worse for fuel econonomy on hilly roads; without any doubt.

Do your own comparisons over same stretch of road doing the folowing

1 Use CC
2 Try and maintain a steady speed like cc (virtually impossible)
3 Drive economically by lifting off accelerator up hill if it follows a downhill section where you can prepare for the hill etc.

CC is best used to maintain a steady speed (thats what it was intended for!), not for fuel economy. Or was it to avoid speed traps !
Cruise Control and Fuel Consumption - Roger Jones
I think the point is that, hilly terrain excepted, the maintenance of a steady speed is a key part of economizing on fuel. Vary your speed frequently and you will undoubtedly use more fuel. Keep it as steady as possible and you will undoubtedly save fuel. Cruise control is quite good at achieving the latter. It's also excellent for ensuring that you are at a speed that won't offend a safety speed camera.

Can't deny the hilly terrain afctor, but I be it's less significant the more powerful the engine.
Cruise Control and Fuel Consumption - DP
This isn't scientific, but I had the use of my father in law's mk4 Golf TDI 130PS for a couple of weeks recently. I decided to experiment to see what effect the cruise control would have on economy.

I did the same journey every day in similar traffic conditions and the cruise set to 70 mph on the motorway, interrupted as necessary. The motorway represents 27 miles of my 35 mile journey. Did one week using cruise, one week maintaining similar speeds "manually"

With cruise (average) = 48.8 mpg on computer

Without cruise (average) = 51.5 mpg on computer

It's quite an eerie feeling having a car with so much torque "accelerating itself" up a hill. Mildly terrifying intially, actually. Never did quite get used to it.

Cheers
DP

Cruise Control and Fuel Consumption - Bill Payer
One of our office ladies has a Passat diesel auto with
cruise control. When she uses it, she finds it very disconcerting
to have the gearbox changing up and down unexpectedly.

I really wouldn't use it (in the UK) in situations where the road is so hilly that it's causing even a diesel VW to downshift.
Apart from anything else, all the other cars going up the hill are likely to slow to lesser or greater extent, whereas the VW will be doing its level best to maintain its set speed. So you'd likely find yourself charging up behind people at a much greater speed than is wise.
I do notice in the US, especially in the hilly parts of California, that the slightest up slope and the US cars tend to downshift. But it really doesn't take much of a hill and they've got the gas pedal to the floor (and are still losing speed!).
Cruise Control and Fuel Consumption - Thinline
Thanks for the replies

It appears that the general trend is 'Yes' but not on hilly roads.

Cheers
Cruise Control and Fuel Consumption - Hamsafar
It isn't called CRUISE control for nothing.
I use it when CRUISING and get better mpg. (about 10% better)

I also use it is areas with SPECS cameras for a safer and more relaxing drive of not having to check the speedo as much.
Cruise Control and Fuel Consumption - Pugugly {P}
Spot on Ashok.
Cruise Control and Fuel Consumption - JohnM{P}

Late to the discussion as usual, so I'll add:
This topic was also debated on the following thread:
www.honestjohn.co.uk/forum/post/index.htm?t=21566&...e
 

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