wrestrepo

I read on Time magazine that one of the strategies for saving gas is to not use cruise control...this was also discussed here until we got tired...In the spirit of believing that I am correct, and having to prove and convince everyone else I am (I feel like talking to my wife now) I would like to revisit this and explain my believes....

It is true that using cruise control will ask the car to speed up (rather accelerate)in an uphill situation to maintain the constant speed...but, what do you think that a person does in those conditions? they will push the accelerator too...I don't think that anyone that considers themselves a good driver would let the car slow down going uphill (I hate it when I get stock behind someone going slow uphill). As a matter of fact, I believe that here the advantage goes to the CC since our feet will try to speed up through the uphill, most of the time going over the "cruising" or desired speed.

In moderate to heavy traffic conditions it comes down to comon sense. I try to avoid it when the drivers around me are being too agresive or there is a lot of stop and go. At the same time, I try to use it as much as possible when people are speeding too much....I find myself becoming part of the "train" cruising at 80 and over to keep up with the pace. This is certainly not condusive to fuel economy and you tipically don't realize how fast you are really going...Again, the advantage would go to the CC since after setting the speed you won't be speeding with the group unless your right foot does it.

Becoming too impatient...well, push the right pedal down a little more...that's what we normally do if traffic seems to be at a stand still even when cruising at normal speed...with CC, "set it and forget it" even if it feels slow, you know what speed you are driving at.

If it is true that CC doesn't work for everyone, I believe that if used properly it will have the advantage over the human foot in fuel economy..jut my

Now, I will be taking an 800 mile trip on my RDX next week (first long one) and I want your thoughts....

spdy0001

RaviNJCLs

iTrader: (4)

I never use CC. And man, do I want a cookie right now.

SakiGT

I hate cruise control unless Im alone on a straight highway. No hills in FL = ok

1. It boosts me to 5lbs - Why?
2. I cant speed up going down a hill or let off when im rolling up one
3. People get in my way and I have to turn it off, go around them, then turn it back on

Ill drive my own car, thanks.

godfather2

i even use cruise control in the city to keep my speed in check. yes, a constant influx of tickets has drastically changed my driving habits

mrdeeno

I think on LONG trips (over 100mi mostly flat highways w/ constant traffic conditions), cruise control probably marginally saves some gas, but over anything shorter or with hills and constant speed up and slow downs hurt gas mileage because when cruise control accelerates the car, it does it more aggressively than a human would (generally speaking anyway).

For example, when I accelerate to increase my cruising speed while not using CC, my car will usually not downshift to accelerate, meaning I am not pushing it hard to accelerate. When I use CC to accelerate or when it accelerates itself (i have intelligent CC), it'll downshift and accelerate to the cruising speed setpoint fast...i think it downshifts 2 gears sometimes depending on how slow it was and what the setpoint is.

fsttyms1

But on the same token (with the cruise on and not disable it) you can accelerate before the hill on your own and hold the gas just above where you would be and not have cruise kick it down a gear and accelerate like it does. I often do.

I use cruise a lot. Its one of the things i have to have on cars with the amount of driving i do

fuzzy02CLS

iTrader: (2)

I use my CC on HW's only. And only if the traffic is light, or I'm not in a hurry to go anywhere.
I find it hard to believe that CC uses more gas. My driving experience with both says it doesn't. Many 100 thousand road miles.

Only POS cars with zero power seem to have problems with hills. Not once has my CLS(3 of them) down shifted going up a hill.

TommySalami

Your cookie has a spider infestation.

260 HP

iTrader: (3)

I actually tested this with my 01 BMW 740i Sport on a trip from my house to San Diego recently (about 110 miles one way). The car had 46k miles when I tested it. I had to go to San Diego a few times in March, so I might as well test the cruise control.

All these trips were made in the evening, so traffic is clear. I found that I save about 1 mpg (from 22 mpg to 23 mpg, about 5%) according to the on-board computer if I use cruise control. I know the on-board computer might be inaccurate, but it's consistent.

I set the cruise control to 80 mph indicated speed (about 76 mph according to my Garmin GPS). I also tried my best to drive at the same speed without the cruise control. Basically, I tried to keep most of the parameters the same. I even used the gas from the same station. The transmission was kept at the Sport mode at all time.

Each test is one round trip of 220 miles. The car had only 2 passengers with no cargo load. The tire pressure was checked in the morning prior to the trip. I kept the tire pressures right at the recommended spec per BMW.

I also let the cruise control do its thing when the car is going slight uphill or downhill. The cruise control was on maybe 90% of the trip.

When I drove the car without cruise control, I tried to drive as conservatively as possible. No sudden acceleration, braking, etc.

YMMV. I haven't duplicated this test using my E46 M3 or my Accord.

mrdeeno

yeah, but how many people using cruise control actually do that? And further, with adaptive cruise control systems my experience is that with moderate traffic, the car will slow down and speed up pretty often depending on how fast the guy in front of you is going or slowing down.

sho_nuff1997

iTrader: (2)

resume button.


i get the same mileage with or without CC. i can't see how a car can get worse mileage with the CC on, unless you have an old car that floors it when u hit the resume button.

Moog-Type-S

mmmmm Chocolate chip spider cookies

dom

Eewwwww

fuzzy02CLS

iTrader: (2)

Try a 94 explorer on a slightly steep hill. The thing actually shuts off the CC cause it can't keep speed.

Sly Raskal

iTrader: (1)

Sly Raskal

iTrader: (1)

Saw it after you pointed it out. I retract my previous post.

BENDER08

i saw the spiders first thinking

Ken1997TL

I've only used CC when driving across the midwest

leftride

iTrader: (1)

2 things i have used less than twice in my car:
cruise control (would rather drive myself)
cd player (ipod)

Trackruner228

iTrader: (1)

I love my CC its great on the highway. There also arent many highways here but if I hit a big hill I can always shift into SS mode and hold 5th gear.

Bearcat94

I use cruise on the highway all the time. In urban/higher traffic areas, I'll kick it off, but in rural areas CC FTW.

2 reasons:

1. I've already made my fair share of contributions to the General Funds/Highway Funds of the various states I travel through. Set it 5 - 7 MPH over posted speed and forget it.

2. When you're sitting in a car for 2 - 5 hours at a time, it's nice to be able to vary your foot/leg position.

My minimum "normal" round trip is 280 miles (single day trip). I also regularly take 300 mile (1 way) trips. Average speed ~65+ mph.

I USED to get 30 - 32 MPG. Got new tires at ~40k miles. Now I am getting ~28 MPG on the same routes.

IOW - having the "right" tires will gain you more MPG than cruise control ever will.

Costco

Try driving on a 2+ hour trip. Your foot will get cramped if you try to keep it at 70 for dozens of miles with just your right foot. I rarely use CC except on long trips with stretches of flat roads.

PortlandRL

When I first started driving, I hated cruise but I've grown to love it to the point I would never buy a car without it. I took the Santa Fe up to Tacoma last Tuesday and on cruise control going up almost the whole way (75 in the 70 zones; 70 in the 60 zones) I averaged 23 mpg. I know if I'd done 70 tops, I would have gotten closer to 25 mpg. We took the RL up to Seattle in February and got 26 mpg average for the trip.

On a side note, I have a friend with an Audi Allroad. As the old Audis had a switch on the turn signal stalk for cruise, he leaves it in the 'on' position all the time even though he rarely uses it. His reasoning? No 'CRUISE' light. My thinking is if you don't have a light, all the more reason to turn it off to avoid inadvertently activating it as you would not know it.

Costco

Sorry but anyone who doesn't know or notice that their cruise is on/doesn't know how to turn it off shouldn't be driving a car with it.

Osamu

I almost never used cruise control when I had it in California. Maybe when I would drive for 1 or 2 hours at 2:00 in the morning up and down the 5 freeway. But even then I think I used it like once or twice just to see if I can tell a difference in mileage, and I never really did, but I never really tried calculating my milage.

But, living in Hawaii, you never are really driving more than a few miles at a time, and my 20 mile commute to work is all uphill or downhill, so I wouldn't use it anyways. Sometimes on the downhill bit, I can just cruise in neutral for like 5 miles.

oh yea, and my current car doesn't have cruise control , and it makes me feel good that I'm not paying for something I would never use.

einsatz

I'm the opposite from most people here, I use it constantly. So much so that I'd like my next car to have adaptive CC. I use it for two reasons... one, I have a lead foot and tend to hit 80 without realizing it. I've already got one ticket on my record, don't want another one. The second reason is the gas savings, which I can say are real, but not that significant - I'm sure if I encountered less traffic they'd be greater.

The trick is to get used to how to time the cancel/resume to traffic without using brakes. Around the beltway here in the DC area I can usually put it on 60 and then use accel/decel to go 1mph up/down for most of the way, and hitting cancel to slow down faster. Cruising this way most of the way and keeping my distance from the car in front I usually have a nicer drive home.

PortlandRL

That's the thing, it has no light whatsoever and the set button is on the end of the turn signal stalk. I've bumped it a few times. Just my

neuronbob

I only use CC on long trips, and do it to give my leg a break. Even then, I follow the instructions in my manual: I don't use it in heavy traffic (unsafe to do that), I don't use it in the rain (REALLY unsafe as it takes your attention away from complee control of the car), and I don't use it in hilly terrain. I make use of those "cancel" and "resume" buttons.