My cruise control is not much chop at keeping to the set speed when going downhill, with a grade of any more than 2 or 3 degrees.

It will close the throttle most of the way but not all the way, and the car will pick up speed unless I hold the CC wand all the way down. Same as you do to reduce your set speed.

AFAICT holding the wand down does fully close the throttle.

It's bloody annoying having to hold the wand down when going downhill.

So why won't the CC automatically do this (fully close the throttle)?

Is this normal/standard operation for 380 CC?

Does it work the same way for you auto punters, or is it just a quirk of the manual?

Can the CC be adjusted or reset so that it will fully close the throttle?

If so, how?

not that i drive a 380 but in my tj i drop it down gears... 3 is good for most grades and i use 2 for those steep ones

Mine is auto, I use tiptronic to go back a gear.

Haven't tried holding the wand down to see if that fully closes throttle and helps hold set speed

I'm talking cruising on the South Eastern freeway in 5th gear at 110km/h, with a contant mixture of flat, uphill & downhill stretches. I could change back 4th gear when going down a hill, but that would be an even bigger hassle than playing with the CC wand or touching the brakes. Especially as it's already doing around 2,900 rpm in 5th at 110km/h, and dropping back to 4th would up the revs to something like 3,400.
I'm mainly asking if it's normal for 380 cruise control to never automatically fully close the throttle, as mine only ever closes it about 7/8 without manual intervention. Fully closing the throttle via the CC wand works to maintain the set speed on all but the steeper downhill stretches, but I shouldn't have to do that all the time!

I have no idea whether it is full or closed throttle - but I find the cruise on the 380 to be fairly average. If I set the cruise @ 110kph it will easily creep up to 118 or 119kph on a downhill stretch that is not particularly steep..

The best cruise I have used was in a FG Falcon Turbo - holds the speed even on a steep downhill

Mate, I think that is normal. TBH I don't think the CC in 380s is all that good except on gentle undulations. I've always given up trying to use it in hilly terrain. However, having lived in Adelaide I would have thought it would be OK on the SE.

Mine likes to kick down to a gear that is almost redlining when it goes up an incline that isn't all that challenging. Very annoying to say the least.

Even with full closed throttle in 5th going down hill your car will speed up, it is something called gravity

Some cars, and very few at that, will automatically shift back through gears to hold speed but that is as I said very few

I simply reach across and tap the tippy shifter back a gear or 3 on very steep hills to maintain speed, this is the only way

I drove a mazda 626 high spec about 23 years ago the the cruise braked for you going down hill, as for closing the throttle, can't help you there, the cc we have is cheap to say the least...

Even with full closed throttle in 5th going down hill your car will speed up, it is something called gravity

Some cars, and very few at that, will automatically shift back through gears to hold speed but that is as I said very few

I simply reach across and tap the tippy shifter back a gear or 3 on very steep hills to maintain speed, this is the only way

No argument Mal, IF the gradient is steep enough. But I'm talking about fairly gentle downhill slopes, around 3 or 4 degrees.

Again, I drive a manual not an auto.

rprodrive & Knotched are the only ones who have even tried to answer my original question.

As rprodrive says, "I find the cruise on the 380 to be fairly average. If I set the cruise @ 110kph it will easily creep up to 118 or 119kph on a downhill stretch that is not particularly steep..".

I'll try again.

Why does the 380 cruise control never fully close the throttle to stop the car picking up speed down a relatively gentle slope?

Even when the CC is trying to prevent the car picking up speed the throttle is still partly open, and this obviously prevents the CC from maintaining the set speed.

At least on my car.

I can make the CC fully close the throttle (and stop the car picking up speed over the set speed) by manually holding the CC wand down, but why won't it do so automatically?

Did MMAL deliberately program the CC to be this way?

Do some other manufacturer's CC work the same (poor) way?

Can it be retuned to work 'properly'?

I would go and see a Mitsu dealer and ask. No one here knows, maybe your car needs adjustment of whatever mechanism the cc uses to control the throttle?
If all 380s are like that,then you should really not use cc where an overspeed situation occurs. Saying "The cruise control made me do it" will NOT get you off a speeding ticket.

I would go and see a Mitsu dealer and ask. No one here knows, maybe your car needs adjustment of whatever mechanism the cc uses to control the throttle?
If all 380s are like that,then you should really not use cc where an overspeed situation occurs. Saying "The cruise control made me do it" will NOT get you off a speeding ticket.

Max,

I'll give it a few days to see if someone here is 'in the know' before I go see a dealer.

Maybe mine is defective, maybe it's normal, I don't know yet. I'm guessing it's normal and MMAL cheaped out on the CC.

Whenever I hit a long steepish downhill (like the downtrack of the SE freeway to the tollgate) I turn the CC off, coz it's effing useless in that situation. Much better just to let the natural drag keep the speed down. If it's steep enough I drop it down to 4th, even 3rd.

Funny thing is, the second to last speeding ticket I got was on the SE freeway about 18 months ago, when I was ambushed by an unmarked cop car and done for 122 in the 110 zone. I had the cruise set for 112 but I wasn't going downhill, I was simply safely overtaking a slowpoke by getting past them reasonably quickly instead of sitting next to them for an eternity. The Plod commented 'you have cruise control, why didn't you use it?'. To which I was sorely tempted to reply 'coz it's much safer to put your foot down and get past the slowpokes quickly'. I was also tempted to reply 'why don't you go and do some real police work instead of ambushing perfectly safe drivers?'. But I kept my gob shut and took my lumps.

No argument Mal, IF the gradient is steep enough. But I'm talking about fairly gentle downhill slopes, around 3 or 4 degrees.


I totally agree with you - even on a slight downhill it will pick up speed very easily. I have the auto. The first time I saw it happen I was like WTF is this - I am doing 109kph and the cruise was set to 100kph (both speed readings from GPS) - and it was only a slight downhill slope.



I can make the CC fully close the throttle (and stop the car picking up speed over the set speed) by manually holding the CC wand down, but why won't it do so automatically?

Did MMAL deliberately program the CC to be this way?

Do some other manufacturer's CC work the same (poor) way?


It must have been calibrated that way - not all cars do it. My last 3 cars (Accord Euro, VE SS and FG Falcon) didn't speed up in the same way on gentle downhills. The first two cars did speed up slightly on an incline but no where near the 'run away' speed the 380 would pick up. Like I said earlier the FG was excellent - but it did apply engine braking to hold speed so that is a different set up.

Speed creep with the CC on downhill happens to me also; so I suspect it is normal. I haven't tried the holding the wand down trick but will now. I do find however that CC is pretty good on holding speed uphill; much better than my previous ride, an AU falcon.

I have only ever driven one type of car where the speed didn't creep up and that is a FG with the 6 speed ZF gearbox.All the Falcon 4 speeds i have had crept up no more or less than our 380.

Hi TreeAdeyMan.

Your problem sounds identical to my experiences, and I know exactly what you are saying. I also have the manual.

With cruise engaged, there is always some residual throttle provided. I get what you are saying ... the cruise could hold speed down steeper slopes if it had the ability to close the throttle completely. I also hold the wand down to maintain speed when the downslope gets past a certain point, it is slightly annoying, but I don't have that problem very often.

Why have they done it? Well there must be a reason, but I'd only be guessing.

As for the general 380 cruise control experience, I don't agree with Knotched about it being poor in hilly terrain. Mine is supremely good, unless of course the downslope becomes any more than slight and the cruise won't completely close the throttle. It is otherwise very, very accurate and very very smooth. I do find it accelerates quite hard with the wand control, but that might be because it was tuned to the longer auto gearing. Even in fifth gear in the manual, hold the wand up and you get quite a kick in the backside. My 3rd gen TL cruise control on the other hand is not so silky smooth, but still okay.

The minimum 40km/h does annoy me.

Hi TreeAdeyMan.

Your problem sounds identical to my experiences, and I know exactly what you are saying. I also have the manual.

With cruise engaged, there is always some residual throttle provided. I get what you are saying ... the cruise could hold speed down steeper slopes if it had the ability to close the throttle completely. I also hold the wand down to maintain speed when the downslope gets past a certain point, it is slightly annoying, but I don't have that problem very often.

Why have they done it? Well there must be a reason, but I'd only be guessing.

As for the general 380 cruise control experience, I don't agree with Knotched about it being poor in hilly terrain. Mine is supremely good, unless of course the downslope becomes any more than slight and the cruise won't completely close the throttle. It is otherwise very, very accurate and very very smooth. I do find it accelerates quite hard with the wand control, but that might be because it was tuned to the longer auto gearing. Even in fifth gear in the manual, hold the wand up and you get quite a kick in the backside. My 3rd gen TL cruise control on the other hand is not so silky smooth, but still okay.

The minimum 40km/h does annoy me.

Thanks flyboy, pretty much confirms that my CC is behaving normally, and I/we just have to put up with the downhill shenanigans.

I agree it's pretty smooth most of the time. Mine gives a tiny jerk when I hit a downhill and the CC throttles back. And yes, increasing speed by holding the wand up gives fairly good acceleration, about 1/2 WOT worth I reckon.

Never tried CC below 60km/h, so the 40km/h minimum is no hassle for me.

I'd just like to comment on the smoothness of the 380 cruise control. I've driven both my 380 and our ASX down to Brisbane now for a couple weeks, and I can say without a doubt that the 380 cruise control is a lot smoother than that in the ASX. In the ASX, on slightly downhill gradients, there is quite a bit of jerking - almost feels like fuel starvation if anyone knows what that feels like. The 380 doesn't do the same thing. It seems to operate smoothly where the ASX does not.

Nobody has said this, so it's up to me.
Cruise control is for cruising, long trip, steady speed, flat road, foot cramp because you haven't moved your foot for a while. Try to use it around town, or in hilly country, and you will be disappointed.

Reminds me of a story - might be true.
Man crashes his motor home. Put cruise control on, went to the rear to make himself a sandwich. It's not automatic pilot, guys!

I fail to read where anyone has posted up saying that they think their cruise control is like auto pilot.

I strongly agree with Disciple in what he says about the 380 CC being smooth as and I do alot of driving, both free way and some driving around town with CC on. Mine will only creep up if it's a very steep down hill slope on a highway, but even then it doesn't go too much faster then the set speed. I have driven quiet a few magna's with cruise control on and the amount of jerking you get from it compared to the 380 which is pretty much none is a huge difference.

Try to use it around town, or in hilly country, and you will be disappointed.

I'm not disappointed whatsoever. I use it ALL the time including around town and hilly country, and it is superb.

In fact, by not using it around town you are losing one of it's best benefits - avoiding speeding tickets.


It's not automatic pilot, guys!

As a commercial pilot, I'm quite aware of the differences between an aircraft autopilot and cruise control - and until someone on the Magna club starts a thread on modding up a toilet for the backseat in the 380, I'm likely to pull over when the need arises :)

Tree Adey Man, I expect the small throttle setting comes from the Mitsi's not wanting the vehicle to coast with the throttle closed for a significant amount of time, especially in the auto.

I know the OP doesn't want to use the tippy when going down a hill, but I suggest that you try it, and a take alook at your instant fuel use gauge at the same time, it may be enough to change your mind, it will help make up for the extra fuel you used to get up the hill in first place.

As for the Third gen users, if you find it speeds up a bit when you first apply the CC, take your foot of first, then set it, it wont increase, this is something they sorted on the 380.

I know the OP doesn't want to use the tippy when going down a hill...mmmm OP has a manual.

Errrr, OK, thanks maggie 3.5, however the resulting instant fuel use remains the same.

:doooh:

...mmmm OP has a manual.

Well spotted Michael!

Instant fuel consumption readout when the CC throttles back going downhill = 5l/100km. Not even close to a fully closed throttle

Instant fuel consumption readout when I hold the CC wand down, or turn CC off and coast (in gear) with nil throttle, or coasting in neutral (ie all with fully closed throttle)= .1l/100km.

So besides the annoyance of having to manually hold the CC wand down to stop it picking up speed down a relatively gentle slope, the way the CC operates downhill is nowhere near optimal for fuel economy.

Some argue that CC is better than almost any driver can manage for fine throttle control to maintain a set speed, others argue that any half decent driver should be able to get better fuel economy with CC turned off.

I find that the 380 'drive by wire' throttle control is harder for very fine control than my old TE V6 was.

So I'm in the first camp - better fuel economy with CC on than off, at least on a long freeway cruise with a few hills involved, such as the SE Freeway. Putting aside the need to manually hold the CC wand down at times.

In the interim, til (if and when) there is a fix, can you flick the stick towards to get a temporary cancel, and flick it up again to resume at the botton of the hill????

In the interim, til (if and when) there is a fix, can you flick the stick towards to get a temporary cancel, and flick it up again to resume at the botton of the hill????

Yep, I sometimes do this instead of holding the wand down. Problem is I often forget that I've cancelled the CC, and once the downhill stretch ends I'm suddenly losing speed!

Just on the using CC vs not using CC debate: It is a known fact that fuel economy is better when not using cruise control as opposed to using it. I recently read an article in a 4x4 magazine where this fuel economy "guru" gave a very detailed explanation of economy driving, CC vs no CC etc. His credentials are he drove a Hyundai Santa Fe across Australia towing a 2 tonne caravan and averaged 4.86L/100km, then to back it up, he drove a Hyundai ix35 on a similar journey and averaged something like 4.2L/100km. In the article it mentioned he did a test with normal, every day drivers, and not using CC, on average, improved fuel economy by 30%. I've noticed the same thing with my 380 - On my old work run by not using CC I would consistantly average around 1L/100km better fuel consumption. I haven't tested this on the highway, because I value my licence too much, on the off chance I'm not looking at my speedo constantly that I stray 3km/h over the limit I'll get a ticket. Every K over is a killer you know, lol.

Just driven Sydney to Toowoomba and a bit of tripping around the Darling Downs area of QLD and checked out this issue over about the last 1500 or 2000 km or so.

I find if I let the overun get to about 8 kmh over the set (110) speed the inst fuel consumtion does rop back to near zero (0.1 l/100k).

It seems to me the CC is exhibiting proportional as opposed to on/off control, which keeps everything nice a smooth without jerks