Cruise Control behaviour

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deian
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Cruise Control behaviour

Post by deian »

Hi,

I was recently going down a steep hill on a dual carriage way with the cruise control set to 75mph...

It keeps to 75mph really well on the straights and up the hills too, it will accelarate up a hill and you can feel the throttle pedal move up and down as it speeds up and it may even change gear itself (being a V6 auto).

But going down this hill it kept to 75mph where a manual car would accelerate if the throttle was steady, it felt as if the car was braking by itself too.... surely this isn't possible?

Or was it the engine braking as it came off the throttle, it was enough to move me forward in my seat. The brilliant part is, it didn't once go over or under 75mph more than 2mph+/-.

Maybe the braking felt was due to the disconnection of torque from the engine?

Deian
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Post by xantia_v6 »

I think it is just psychological. Your subconcious expects the car to slow down uphill and speed up downhill.

There is a road near here with a sharp uphill then downhill then uphill then downhill spaced over a few hundred metres. With the cruise control on it feels like you are sitting at the front of a rollercoaster, acelerating on the uphills and decelerating on the downhills.
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Post by deian »

I think you could be right, because we are not in control i.e not on the pedals it feels quite weird.
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Post by James.UK »

I tried the cruise control on my Accord once! It scared the heck out of me!! It does exactly what it sez on the box, but it's as if you are a passenger sitting in the wrong seat!! lol.. I haven't used it since.. :roll:

I like being in total control when driving.. heh heh.. :lol:
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Post by Homer »

I imagine it was down to engine braking. The auto box will have some kind of lock-out at those speeds and behave like a manual.
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Post by f00lzz »

One of the features of this autobox is that it provides engine braking when slowing down just like a manual box.. whether in CC or not. This is a fantastic autobox in my opinion and one that is a joy to use.
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Post by rossnunn »

James.UK wrote:I tried the cruise control on my Accord once! It scared the heck out of me!! It does exactly what it sez on the box, but it's as if you are a passenger sitting in the wrong seat!! lol.. I haven't used it since.. :roll:

I like being in total control when driving.. heh heh.. :lol:
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You'll not be liking this much then!! http://www.youtube.com/watch?v=U88UlyjM4Pc
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Post by jgra1 »

i watched a rerun of a nightrider episode last night, 'autocruise' button was good ;)

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Post by mooseshaver »

rossnunn wrote:
You'll not be liking this much then!! http://www.youtube.com/watch?v=U88UlyjM4Pc
Heh, I can imagine the Citroen version now, 70MPH in the fast lane, Oh No Anti-Pollution fault, and suddenly its given you back the wheel and you can't go more than 30MPH.
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Post by lolingram »

Driving cruise control needs to be learnt, and is only REALLY effective when coupled to an Auto box. On the European roads away from traffic jams, it is regal, as one can drive and move your legs around on long journeys - using the hand controls only - a bit like a handicapped control system at first.

Horses for courses, but you need to persevere - a bit like learning left foot braking, which is the correct way to drive Auto.
I tried the cruise control on my Accord once! It scared the heck out of me!! It does exactly what it sez on the box, but it's as if you are a passenger sitting in the wrong seat!! lol.. I haven't used it since..
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Post by deian »

Left foot braking? For real???
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Post by jeremy »

As a matter of interest (and assuming 2 properly functioning limbs) why would you want to left foot brake?

The official guide published by the Department of Transport (or whatever it is this week) recommends that the right foot is used except for maneuvering at low speed. Having had automatics in the past I can't really even see the point in that if the vehicle is functioning properly.
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Post by deian »

It's a technique in racing to brake with ur left foot, and thats all i know.

When I first got into the V6 when buying it I automatically braked with my right foot because i drive a forklift at work.

So after re-programming myself to brake with the left foot again, it was all fun and games on the forklift the next time.
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Post by jeremy »

Forklifts are more fun with 3 pedals, when the left one operates reverse!

Having done a nosedive when I went to change gear on an automatic and tried to use the brake as a clutch with my left foot I make a point when I drive the things of planting my left foot well out of the way and leave it there!
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Post by deian »

I wonder what happens if you press forwards and reverse at the same time on one of them?

We have three pedals too... two are the brakes, it's more car like really, the proper brake is in the middle like cars, and the one on the left just disconnects the gearbox so you can lift up the heavy stuff while driving without driving into anything else, pressing it more will push the brake.
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