vincethe1

it is instant, as soon as you release the gas pedal (fully), the fuel cuts, that's how the engine starts decreasing it's rpms.

in a manual, try this, put ur car in like 4th gear at like 50mph or so, and let go of the gas, now, turn off the ignition and you will see there will be no difference in the deceleration and feel of your car, when you turn the ignition back on though you might feel a kick as the car rams fuel into the injectors preparing to "start" because it's designed to start from 0...and that's also why u waste gas on starts.

your power steering and power brakes will still work with the ignition off, because the engine is still being rotated by the wheels....however don't try completely taking the key out of your ignition if you try it because you are in danger of locking your steering wheel.

again, this is all to be done in a manual car, an automatic will usually disengague the transmission as soon as you turn off the ignition.

mio

its 15 secs or 45 secs? i remember its 45 secs... not so sure...

but anyways... always start ur car and turn off ur car is not good for ur engine...

mio

but how do u know if ur gonna wait for more than 15 secs or less than 15secs...

SouthernBoy

Somewhere between the end of June '98 and early July '99 I was going to work one morning, traveling north on route 28 from Centreville to Ashburn, VA where I worked. Route 28 had a 55 MPH speed limit and was a major divided highway which carried all kinds of traffic.

I had come to a stop at a T intersection light, just north of the intersection of route 606. I was in the left inside lane of 4 lanes.. the other three lanes were filled with traffic waiting for the light to change and I was the only car ('96 Ford Contour) in the left center lane.

Looking in my rear view mirror, I saw an 18-wheeler flatbed truck with two or three large cement sewer sections, change lanes from the right center lane to my lane because the other lanes were stacked up. He was traveling perhaps 60+ MPH and in no way was he going to be able to stop. The light was still red.

I immediately moved over in front of the car in the far left lane to clear my lane and the truck went through the red light at a high speed. Fortunately no drivers who had the green light were in his way when he went storming through the red light. THIS is the primary reason I would never consider or entertain turning my engine off at a red light. You could also add to this the fact that you might have to get away from BGs (bad guys) who are looking for their next victim.

Gentlemen, best not to court disaster or evil. Leave your engine on while waiting out a light.

Legend2TL

No, as soon as the throttle is closed the fuel injectors are turned off. Below is from the 2005 TL Acura shop manual.

http://www.flickr.com/photos/9896658...00615/sizes/l/

AcuraATLBoi

I'm going to try this!

Legend2TL

Actual scan

redman042

Wow... incredible story, and pretty much closes the book on this discussion in my mind. I once avoided a rear-ender by moving out of the way as well, but it was nothing like this story. You probably saved your life that day by paying attention to your mirror and reacting, and I'm sure that truck driver was beyond surprise and relief when the car he was certain to hit suddenly jumped out of his way.

erick3

...so uh what's the consensus? haha is shutting off your engine at the light useful when it comes to saving gas???

SouthernBoy

I would wager that I would have been killed had I remained in that lane, oblivious to the rapidly approaching truck. I feel certain the reason he changed lanes was because I was the only one in my lane and he would have only hit one car instead of maybe 6 or eight of them (bowling anyone?).

One of the concepts I have tried to drill into my wife and daughters is this. ALWAYS BE AWARE OF YOUR SURROUNDINGS. When driving a car, this is so critical. I use to tell them that if you see someone coming up on you fast, get out of the way and let them hit the vehicle in front of you. This might sound cruel to the sensitive types, but it's real life. I can relate quite a few other times when being aware of my surroundings has kept me out of trouble and/or kept me alive.

Funny. During and after an incident such as the one I just told about the truck, I don't get nervous. First off, when it is actually happening, there's no time for getting nervous. And after it's over and you're still alive and Ok, why would you get nervous then? This has happened every time to me in dangerous situations.

Now if I am in a car and someone else is driving when a bad thing starts to go down, I really get anxious.

fsttyms1

I agree and leave mine running for that very reason. Ive avoided being rear ended numerous times. I would never shut the car off to save the minuscule amount of fuel. In fact i leave it run all day usually while working just to save on the starter. (i would be starting and shutting off every 10 15 min or so) The TL will burn 1/8 to 1/4 tank with the AC running in a 8 hr day.

AcidHorse

That's really pathetic. Shutting off your engine at stoplights to save gas whereas these lights last for about 30-45 seconds or so? How much volume of gas are you going to save?

People who do this cheapo way don't deserve to drive the almighty TL. Trade your TL in for a 95 corolla or 92 Geo Metro if you're so concerned about saving gas.

black label

I highly doubt all the oil will drain into the pan leaving the engine completely dry in the time it takes for a light to turn green.

The worst engine wear occurs during a "cold start", if you shut it off for 2 minutes at a stop light the engine isn't going to go cold.

I'm going to have to agree with Southern Boy on his argument for why you shouldn't do this. The only time I shut my engine off in the street is at a draw bridge as you typically sit there for about 10 minutes and you have no where to escape to anyway.

TOTAL~LUSH

http://www.motherjones.com/news/feat...permilers.html
Read the 4 page article.
http://www.cleanmpg.com/forums/showthread.php?t=1510
Scroll down 1/3 to section II and III and read this stuff.


I have been looking into this for a while now and read allot of stuff about hypermile drivers. It is pretty interesting that these guys get over 100 mpg in a prius or a civic.
I dont agree with shutting off your engine for a few seconds. Drafting behind semis on the highway, slow accelerating and timing the stop lights i agree with.
there are allot of things these guys do that seem crazy but some of it does make sense and they have proved it works.

LaCostaRacer

I have completed this experiment with cutting the motor at appropriate times durinig
my commute. The results of this tank are as follows:

Miles: 268
Fuel: 12.844 gallons
Actual MPG: 20.86
MID MPG: 21 (notice how accurate MID is: well within +- .5 MPG do to rounding)
MID MPH 28

My last 5 tank average was: 20.36 so cutting the motor got me a big whopping
.5 MPG improvement over the average or 2 MPG improvement over my worst tank of
of the five previous which was 18.8 MPG. I had the A/C on a lot this tank and
had many cases where I had others in the car so I didn't always cut the motor
like I may have if I was only driving.

So this practice does help but it doesn't make a huge difference based on my
experience. It makes a better difference picking routes and slowing down
when you see oncoming Red lights and so forth.

Many people pointed out the negatives of this practice as being safety, wear
and tear on the starter/motor and so forth. Most of us won't be keeping our
cars long enough to experience the wear-and-tear argument but I have not
counter on the safety argument- it's a very valid one. I will cut the motor
when it makes sense and not when it doesn't.

I'll cut the motor at key situations where I know the motor will be idling for 2-5
minutes and possibly more in the winter. One great time to cut your motor is
when you're waiting to refuel the car. It takes at least 5 minutes for most
people to refuel their vehicles. Another good time is waiting to make a left
turn at a busy intersection that has islands and you're already encased with
cars all around you anyway.