Quote: Originally posted by naturlist123 on 03/12/2016
when going down hill cruise control throttles back engine revs same when aqua planing + anti skid control also trottles back engine revs as well as adjusting brake alignment.
That very much depends on the car. When mine is going down hill the revs stay appropriate to the speed, so if the car's speed starts to exceed the cruise control's set speed, no engine revs are needed and the revs will already have gone back to idling. If the car continues to accelerate due to the incline, I will have to brake, which will cut out the cruise control anyway. Other cars will vary from this.
The new adaptive cruise control systems are actually capable of using the brakes automatically to keep the speed in check, in the same way that they're capable of applying the brakes if the car in front of you slows down. Don't ask me how it works, I'm not that clever!
To answer the OP 'is it safe' as far as I can see it's just as safe to use cruise control when towing as when driving solo.
NOT more economical, though. To get the best economy out of a fuel injected engine you need to spend as much time as possible using zero acceleration. A cruise control system does the opposite in that it constantly adjusts the throttle to keep the speed constant, with the result that more fuel is being injected into the cylinders. This issue can only be magnified if you're towing.
I always use the cruise when towing but I find that if I re engage say coming out of a roundabout at say 30mph it will accelerate back up to the cruise speed faster than I would and so I would say it would burn more fuel as a result.
I tend to get back up to the cruise speed manually and then re engage cruise to maintain the speed.
Quote: Originally posted by Grampian91 on 22/11/2016
The loss of traction as you float on the surface of the puddle can increase speed because you have now eliminated the friction of the tyres on the road.
Without friction its possible to pickup speed without having to accelerate.
Wait until you get an icy carpark thats flat. You can push your car with one hand and it will gain momentum very easily.
only if there's a gradent. your vehicle will not get faster on a flat icy surface without applying an increasing amount of force.
------------- Doing whatever the rice krispies tell me to.
Quote: Originally posted by Nellie72 on 09/12/2016
Quote: Originally posted by Grampian91 on 22/11/2016
The loss of traction as you float on the surface of the puddle can increase speed because you have now eliminated the friction of the tyres on the road.
Without friction its possible to pickup speed without having to accelerate.
Wait until you get an icy carpark thats flat. You can push your car with one hand and it will gain momentum very easily.
only if there's a gradent. your vehicle will not get faster on a flat icy surface without applying an increasing amount of force.
Quote: Originally posted by woodman2 on 07/12/2016
I always use the cruise when towing but I find that if I re engage say coming out of a roundabout at say 30mph it will accelerate back up to the cruise speed faster than I would and so I would say it would burn more fuel as a result.
Because you not using it as Cruise Control, i.e. holding a specific speed, resuming CC as you depart a roundabout is basically using the CC as a hand accelerator.
Quote: Originally posted by ad210358 on 18/12/2016
Quote: Originally posted by woodman2 on 07/12/2016
I always use the cruise when towing but I find that if I re engage say coming out of a roundabout at say 30mph it will accelerate back up to the cruise speed faster than I would and so I would say it would burn more fuel as a result.
Because you not using it as Cruise Control, i.e. holding a specific speed, resuming CC as you depart a roundabout is basically using the CC as a hand accelerator.
Correct.
It is far too aggressive at resuming a given speed, so I always manually attain the speed and then engage CC.
Some cruise controls work differently to mine it would seem. I can only accelerate up to the speed I want to cruise at, then press a button to engage cruise control. If I slow down, say for a roundabout, it is immediately cancelled. If I have it set for say 50, I can accelerate beyond it to pass another vehicle, then when I take my foot off the accelerator it will drop back down to 50. To slow below 50 I can either switch it off or touch the brake. How can you accelerate using cruise control?
Quote: Originally posted by Colin21 on 21/12/2016
Some cruise controls work differently to mine it would seem. I can only accelerate up to the speed I want to cruise at, then press a button to engage cruise control. If I slow down, say for a roundabout, it is immediately cancelled. If I have it set for say 50, I can accelerate beyond it to pass another vehicle, then when I take my foot off the accelerator it will drop back down to 50. To slow below 50 I can either switch it off or touch the brake. How can you accelerate using cruise control?
Try engaging CC at a speed below what it is set at.
Mine has a "Resume" button which will then accelerate back up to the speed it is set at. It is a bit too aggressive at attaining the speed so I don't use it.