Does Cruise Control Really save Gas?

[Thermo1223]

I personally can't stand anyone who loses speed going up hills because all it does is cause a chain reaction with every person who isn't paying attention to slam on their brakes or cut into my lane of travel.

Cruise control stays on no matter what unless traffic dictates otherwise. Then again I can choose what gear I'm in so maybe that's why but you are gonna use fuel climbing hills no matter unless your a doofus that does 40mph in a 65 zone.

 

[IndyIan]

I guess I was thinking more of how cruise control could hurt or benefit mileage.
The cars I've used it in seem to maintain speed pretty easily but I'd still be interested watching what its doing on my scanguage as 2 or 3% differences in throttle openings make 10-20% differences in instantaneous mileage for steady speed highway cruising.
If you read the link I posted, you can see why pulse and glide is such an effective hypermiling technique and I think even a small variation in speed that might happen with a cruise control system could have a small pulse and glide effect as well.

 

[morris]

in 1984 i bought a new plymouth gran fury. it didnt have a cruse, but the wife wanted one. so we had the dealer put one on, BIG MISTAKE. the aftermarket cable to pull the carb was clamped to the stock flexing cable that pulls on the carb. it flopped around like a chevy valvetrain. i went back to the dealer, and raised [censored]. they put a better one on, same price

 

[mechtech2]

We have to consider the benefits of AC or cruise control, even if there is a loss in MsPG.!

 

[mechanicx]

I think a better way of describing it would be it set a fixed "throttle" angle, so both engine speed and road speed would be allowed to decrease up grades and vice versa. I guess the theory is you would then end up with about the same average speed and fuel milage as if driven over a flat road. Assuming the average grade didn't increase.

 

[eljefino]

Originally Posted By: Thermo1223
I personally can't stand anyone who loses speed going up hills because all it does is cause a chain reaction with every person who isn't paying attention to slam on their brakes or cut into my lane of travel.

Cruise control stays on no matter what unless traffic dictates otherwise. Then again I can choose what gear I'm in so maybe that's why but you are gonna use fuel climbing hills no matter unless your a doofus that does 40mph in a 65 zone.


It's a challenge on a road like I-80 with two lanes per direction and tons of hills, with 18 wheelers in the right lane making about as good average time as the cars in the left. Since the drivers presumably know the road and the valleys, they let 'em rip down some grades to make it further up the next hill.

Polite things like lane etiquette are mostly thrown out the window. I just try to be consistent, this translates into not obstructing, and not using cruise. They seem happy to goad cars into speeding down the right lane, and I'm happy to oblige.

 

[Craig in Canada]

Originally Posted By: IndyIan

If you read the link I posted, you can see why pulse and glide is such an effective hypermiling technique and I think even a small variation in speed that might happen with a cruise control system could have a small pulse and glide effect as well.


If "pulse and glide" becomes a popular trend I hope they open special "pulse and glide" lanes so the rest of us don't have to put up with it in the flow of traffic. We already get enough unintended "pulse and glide"/stop-and-go due to sheer traffic congestion.

 

[IndyIan]

Originally Posted By: Craig in Canada
Originally Posted By: IndyIan

If you read the link I posted, you can see why pulse and glide is such an effective hypermiling technique and I think even a small variation in speed that might happen with a cruise control system could have a small pulse and glide effect as well.


If "pulse and glide" becomes a popular trend I hope they open special "pulse and glide" lanes so the rest of us don't have to put up with it in the flow of traffic. We already get enough unintended "pulse and glide"/stop-and-go due to sheer traffic congestion.

Cranky commuter eh!

I was thinking more of a 3-5 mph oscillation in speed when not in morning traffic...
It would be more to take advantage of the fact the engine is more efficient at 50%+ throttle and maybe on the "coast" the engine does some lean burning which its not allowed to do under normal load.
I'll have to try it for a tank or two in the Neon and see if it works.

 

[Nick R]

I hate driving behind people who can't maintain speed. The left lane here is generally a flat 75MPH +/- 2. Cruise control. When someone comes in who doesn't know how it works, it's 70....80...65.... Then everyone passes them on the right when they don't get out of the way.

 

[Craig in Canada]

Originally Posted By: IndyIan

Cranky commuter eh!

Actually I commute via city bus, train and foot, eh!

The only job I commuted to via car was a four month internship. Everything else has been public transit or exclusively on foot (those were the days).

Quote:

I was thinking more of a 3-5 mph oscillation in speed when not in morning traffic...


Where it does bother me most is road trips where I *do* want to use cruise control or at least drive steadily. Then you end up stuck behind someone with no throttle control, low situational awareness, or whatever other affliction causes their speed to constantly fluctuate.

 

[IndyIan]

I find I just leave more space when behind someone regardless of what they are doing, sitting on the ground in the Neon, its the only way to see the full situation. It also allows me to coast on the hills without wasting momentum hitting the brakes to maintain a specific distance off their bumper.

 

[Spazdog]

+1

More like 70...75...80...85...OMG LOOK HOW FAST I'M GOING [BRAKE HARD]55...60...65...75...[BRAKE HARD]

 

[123Saab]

Definately makes a difference in My ranger on the Hwy.

Not by tons, but around 1-2 mpg.

 

[HTSS_TR]

It may not save much gas, but it does save getting speeding ticket(s) and a relax driving experience. California Highway Patrol gave a lot more traffic tickets in 2010 than any previous year.

 

[Thermo1223]

Originally Posted By: eljefino


It's a challenge on a road like I-80 with two lanes per direction and tons of hills, with 18 wheelers in the right lane making about as good average time as the cars in the left. Since the drivers presumably know the road and the valleys, they let 'em rip down some grades to make it further up the next hill.

Polite things like lane etiquette are mostly thrown out the window. I just try to be consistent, this translates into not obstructing, and not using cruise. They seem happy to goad cars into speeding down the right lane, and I'm happy to oblige.


We have a few sections like that around here, most OTR guys stick to the right lane so we can freely pass once they start dropping below 50 in a 65 zone. Some loaded rigs tend to creep up the hill at 40

Every now & again you do get someone in the left lane pacing the truckers...you can only imagine how idiotic people get then.