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Discussion Starter · #1 ·
I use the cruise control when trying to keep a steady speed in 30mph and 40mph limits where it's easy to stray into the "points on the licence" zone.
I have noticed that, in auto, when I engage cruise at these speeds it drops a gear, from 4th to 3rd, or 5th to 4th, for example, and then it feels like the revs are too high for just pottering along. If I want to keep in the higher gear that it was perfectly happy at, before cruise was activated, I have to switch to manual mode.

Is this normal behaviour (I don't mean the pottering along at low speeds, I know you're all thinking mean thoughts about that ;)) ?
 

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Why don’t you set the speed warning alarm rather than use cruise control? It just takes a few more seconds to set before you move off at the start of the day. The car will do what it feels is best when left to its own devices. That’s the way it has been programmed. It’s avoiding unnecessary strain on the engine and gears.
 

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Why don’t you set the speed warning alarm rather than use cruise control? It just takes a few more seconds to set before you move off at the start of the day. The car will do what it feels is best when left to its own devices. That’s the way it has been programmed. It’s avoiding unnecessary strain on the engine and gears.
With the top of the spider off, I cannot hear the speed warning beep in my car.
 

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With the top of the spider off, I cannot hear the speed warning beep in my car.
Buy a coupe? 😂 Who has ever used the speed warning? (Not me)There’s an engine note that’s loud enough to tell you your speed even for my damaged ears. I would have thought the speed warning was the same as the annoying seatbelt warning. It’s hard to ignore that.
 

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1. I always forget mine has cruise control.
2. My speed warning is set to a fairly high speed because of how easy it seems to get up there when merging onto the expressway.

From a few things I've seen online, it's best to keep direct injection engines higher up in the rev range to prevent low speed pre-ignition.
 

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I use the cruise control when trying to keep a steady speed in 30mph and 40mph limits where it's easy to stray into the "points on the licence" zone.
I have noticed that, in auto, when I engage cruise at these speeds it drops a gear, from 4th to 3rd, or 5th to 4th, for example, and then it feels like the revs are too high for just pottering along. If I want to keep in the higher gear that it was perfectly happy at, before cruise was activated, I have to switch to manual mode.

Is this normal behaviour (I don't mean the pottering along at low speeds, I know you're all thinking mean thoughts about that ;)) ?
Hi @Anglospider - yes this is perfectly normal and depends entirely upon whether you are in Manual or Auto modes and the position of the DNA selector.
If you want it to just purr along in the highest gear possible you will have to select N (or dare I say it A if the weather and road conditions dictates so) for the ECU and TCU maps to agree that it's OK to hold a higher gear.
If you have it in D or Race modes with the cruise control on, then the ECU and TCU assume that throttle response and immediate power delivery are more important than fuel economy and lower noise levels when transiting through one of your pretty English villages.
Cheers,
Alf.
 
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From a few things I've seen online, it's best to keep direct injection engines higher up in the rev range to prevent low speed pre-ignition.
I think the rev number is down near 1200. The better ECU and TCM's will downshift at RPMs too low, and which risk this detonation. The risk is in true manual trans cars and boneheads stomping the throttle at 1,000 RPM... in longer gears.

We can't do anything that dumb. We got 'puters gatekeeping us.
 
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You guys have cruise control? Next you’ll tell me you have parking sensors too. Some of us have true sports cars with none of that fluff, just adds weight anyway.

;)
Did you complete that project to convert your car to hand crank and hand pressurized fuel tank? These are the mods I want to see! :p

Bring back manual chokes!
 
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I use the cruise control when trying to keep a steady speed in 30mph and 40mph limits where it's easy to stray into the "points on the licence" zone.
I have noticed that, in auto, when I engage cruise at these speeds it drops a gear, from 4th to 3rd, or 5th to 4th, for example, and then it feels like the revs are too high for just pottering along. If I want to keep in the higher gear that it was perfectly happy at, before cruise was activated, I have to switch to manual mode.

Is this normal behaviour (I don't mean the pottering along at low speeds, I know you're all thinking mean thoughts about that ;)) ?
This is the opposite of my car. I can be in Auto and Dynamic mode and it will upshift from 4th to 5th as soon as I engage cruise control. The only time I would think it would downshift is if you keep lowering the speed via the stalk and it believes it will start to lug. Or maybe a steep hill creating a similar lugging condition.
 

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This is the opposite of my car. I can be in Auto and Dynamic mode and it will upshift from 4th to 5th as soon as I engage cruise control. The only time I would think it would downshift is if you keep lowering the speed via the stalk and it believes it will start to lug. Or maybe a steep hill creating a similar lugging condition.
He’s engaging cruise control for 30-40mph speeds, so no wondering there.
 

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Discussion Starter · #17 ·
Seems like it’s just one the quirks of the car, then, I’m not going to lose sleep about it :)
 
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That is to be expected, as the system is set to be able to accelerate a bit if you go uphill. That would not be preferred at very low revs.

And yes, I am very happy that I opted for cruise control and reversing sensors, since I have done more than 100.000km in mine :cool:
 
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Per the manual it is capable of regulating the speed from 19 to 105. The CC is pretty consistent with other vehicles I've had. I messed around a bit tonight in Dynamic/Auto with the AC on. It held 25MPH in 3rd without wanting to hunt around. It also stayed in 4th from 30MPH to about 43-44MPH before moving to 5th.
 
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