Does rapid acceleration from stop & go lights hurt fuel economy?

Reply

  #1  
Old 04-14-06, 04:29 PM
DaVeBoy's Avatar
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Mar 2006
Posts: 1,665
Does rapid acceleration from stop & go lights hurt fuel economy?

I know that in pre-fuel injection era cars, it did. But what about cars that have either throttle body fuel injection or the individual port fuel injection?

At near $3 a gallon again (*sheesh!), I take off like I have a raw egg between my foot and my gas pedal. I have throttle body injection.

Everybody around me though drives like a bat out of hell. I'd sure hate to think that these people are causing gas prices, that I have to pay for, to go up, due to their rapid accelerating.
 
Sponsored Links
  #2  
Old 04-14-06, 04:53 PM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,017
The easier you are on the gas and brake the easier you are on the engine = better mileage. The smaller the engine versus weight the bigger the difference will be.
 
  #3  
Old 04-14-06, 09:17 PM
LouBazooka's Avatar
Member
Join Date: Dec 2005
Posts: 553
Originally Posted by DaVeBoy
I know that in pre-fuel injection era cars, it did. But what about cars that have either throttle body fuel injection or the individual port fuel injection?

At near $3 a gallon again (*sheesh!), I take off like I have a raw egg between my foot and my gas pedal. I have throttle body injection.

Everybody around me though drives like a bat out of hell. I'd sure hate to think that these people are causing gas prices, that I have to pay for, to go up, due to their rapid accelerating.


fuel economy is a relative concept, there are ways to optimize your car's fuel consumption like proper tire inflation, regular tune-ups etc., flooring the pedal at the green light is definetely not one of them.
 
  #4  
Old 04-15-06, 02:56 PM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,513
There is, however, a school of thought that it is better to accelerate to your intended speed in a brisk manner [not pushing the gas pedal through the floorboard, but somewhere between there and taking 2 miles to go from 0-35 mph], since your best gas mileage is when cruising.

In my case I can only improve on the 8 MPG downhill with a stiff tailwind.
 
  #5  
Old 04-15-06, 03:28 PM
DaVeBoy's Avatar
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Mar 2006
Posts: 1,665
So could I assume that all responders so far are in agreement that irregardless that fuel injection is computer monitored for proper ratio...that even considering that, it is still wasteful to really step on the gas? I am actually wondering why, from the technical aspect...that if it is truly metered properly for different driving conditions, as to how this would be wasteful.

I'm not sure about 'the_tow_guy's theory tho, about reaching cruising speed faster. It seems like I have recalled hearing that in the past, also. But I wonder what would make this to be so, since for every block the slow car would be going would be at a less speed than the guy doing 55...and the fact that the wind resistance wouldn't be there, also.

For each car to reach 55 mph from a dead stop, the faster car would have to be pressing down more on the gas pedal on average, the whole time, as opposed to the slower guy. Right? (Or am I wrong?) Or do you think that once a car reaches that 55 mph cruising speed that the gas pedal would actually be held down LESS?? than that of the slow driver who is accelerating at 5.5 mph hour per block for 10 blocks (let's say)?
 
  #6  
Old 04-15-06, 07:29 PM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,513
You have got ENTIRELY too much time on your hands!
 
  #7  
Old 04-15-06, 09:19 PM
Member
Join Date: Dec 2001
Posts: 2,538
try to explain it this way the computer controls on your car do help slightly to improve gas mileage by keeping the fuel ratio correct in most driving conditions however when flooring it or accelerating hard it is usually programed to run a bit richer for good performance.
have read about several old vehicles converted from carburation to modern fuel injection to only gain 1mpg just to give you an idea of how much the electronics help.
 
  #8  
Old 04-16-06, 07:07 AM
Member
Join Date: Aug 2003
Location: Cape Cod
Posts: 4,320
[QUOTE=DaVeBoyDoes rapid acceleration from stop & go lights hurt fuel economy?[/QUOTE]
Yes
AAA has the latest test
It's quite mind boggling how badly some cars/trucks did when driven like that

As for the "up to cruise quickly" saving fuel, it was a theory that appeared about the time FI started appearing (mid-80s)
Although it had a basis in logic, and was touted by engineers of the time, in reality it has not proved to be true for real world drivers
 
  #9  
Old 04-16-06, 12:08 PM
DaVeBoy's Avatar
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Mar 2006
Posts: 1,665
Thanks guys.

And "tow", yes I do have too much time on my hands. And I've always been this way. You would not believe all the stuff I have tried to analyze in my life. To why perpetual motion machines don't work... to how depth of a well affects electric consumption... or how distance/size of pipe affects how much the water volume gets reduced, and starting a 'log' on this and conducting experiments. Regarding cars, I have tried to...aw heck...I'll just start a new thread on this and see what you guys think.
 
Reply


Thread Tools
Search this Thread
Display Modes
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 01:47 PM.