Cruise Control W210, use more or less fuel?

[imbck666]

Many different answers on other forums to this one.

On a 1850mile road trip to Turkey in summer and back 2022 Miles I noticed that whilst CC was on set at 70 my w210 consumed slightly more fuel than without CC.
Is it because CC uses more electricals to keep speed up ? sensors etc.. so more electrical usage so harder on engine ?

I always thought CC would use less fuel (and just for everyone i was on flat roads, no CC on hills) so before anyone gets into uphill CC usage malarchy I just thought I'd state it.

Thanks

 

[brigadier]

I guess it depends on how steady your right foot is. If you drive very smoothly without unnecessary acceleration or braking it's possible

 

[flango]

Every car I have had that has had cruise control has used more fuel when using cruise than without. I was regularly doing 1400 miles per week between Yorkshire and Ayrshire and ran numerous tests on this subject and the 3 cars I had at that time A Subaru legacy Outback 3.0, A Volvo T5 2.5 and a Seat Cupra 1.9Tdi were all worse on fuel on the same run at the same speed, Subaru used about 10% more< Volvo about 7% and Seat 3%

So my conclusion if you are a good considerate driver and use acceleration sense and avoid heavy breaking then cruise will increase your fuel consumption. I put mine down to the fact that also a set of brake pads last me up to 70,000 miles, just my humble twopenneth though

 

[Dieselman]

CC uses more fuel because it is always correcting the speed, including slowing then speeding up again, whereas a driver will allow the speed to vary depending on terrain and wind resistance.
For example the CC will slow a car going downhill only to speed it back up again going up the next one, whereas a driver will allow the speed to creep up downhill in anticipation of the climb.

The big word in fuel economy is anticipation.

 

[trapperjohn]

Being a lazy bottom I use CC whenever I can. Its great to have data backed answers on here. Ill take that few more MPG into consideration as I waft about my luxury lifestyle.

Thanks you. Happy Cruising.

CHEERS

 

[paul73mt]

CC uses more fuel because it is always correcting the speed, including slowing then speeding up again, whereas a driver will allow the speed to vary depending on terrain and wind resistance.
For example the CC will slow a car going downhill only to speed it back up again going up the next one, whereas a driver will allow the speed to creep up downhill in anticipation of the climb.

The big word in fuel economy is anticipation.

+1 but what is the best speed/mpg combination ????

 

[renault12ts]

The big word in leg ache is CC...I wouldn't be without now.

 

[trapperjohn]

Best "click to click" for my 99 300TD Estate was 40 MPG. That was driver only and a weekend bag. CC was set at 2000RPM which on my motor is 60MPH give or take. All tyre pressures were correct for a lightly loaded car. Tyres though were cheap Chinese on the back and a Conti and a Goodyear on the front axel. All tyres were 16s" and 255.

It was the tail end of September this year from Glasgow down the Lancashire.

 

[renault12ts]

Best "click to click" for my 99 300TD Estate was 40 MPG. That was driver only and a weekend bag. CC was set at 2000RPM which on my motor is 60MPH give or take. All tyre pressures were correct for a lightly loaded car. Tyres though were cheap Chinese on the back and a Conti and a Goodyear on the front axel. All tyres were 16s" and 255.

It was the tail end of September this year from Glasgow down the Lancashire.

255s? What profile?

My best is over 50mpg at just below 60mph average.

 

[trapperjohn]

Sorry my mistake 215 55 16s. The 320CDI is always better than the 300TD on long distance MPG.

 

[Paul/]

The big word in leg ache is CC...I wouldn't be without now.

Only a generation ago, driving even a small car was an opportunity to exercise the limbs (unassisted steering, sticky manual handbrake, heavy clutch...)- now we don't even have to hold our foot in position on the gas- the most taxing effort is keeping a finger or two on the steering wheel.

Like the invention of the TV remote, the development of the motor vehicle is threatening to degenerate the human race. Heavy shopping is our only salvation- Buy More Bottles.

 

[V12]

Please show me a flat road and I'll believe that cruise control uses more fuel in a like for like comparison.
In real world usage of course no cruise will be much better.

Sent from my GT-I9300 using MBClub UK

 

[paul73mt]

i'm on 225/40/18 front and 255/35/18 rear all Pirelli PZero Rosso and averaging around the 1500rpm (around 50ish mph i think) I return high 40's

 

[imbck666]

Many answers reveal same opinions =)

Guys thanks for all the answers, that sums up my consumption as well