Anyone noticed how slowly these cars deccelerate when you take your foot off the gas? Anyone bothered by having to use the brakes to slow down when the engine should provide some decceleration?

This is the first automatic transmission car I've had and that is the only part bothering me. I can feel that there is some sort of circuit kicking in when you let your foot off the gas that keeps a bit of throttle on (or air fed in). This is undoubtedly done for emissions control purposes, but it of course makes the car less responsive. Back in the 70's and 80's when cars had carburetors they had a device called a dashpot that did the same thing, but that was easily defeatable. Anyone been into the injection/intake system enough to find out how this is being accomplished on our TLs, and of course how to defeat this function?

 

dude you worry too much.

If you really want to feel engine braking, put the gear shifter in "3" or even better in "2" and enjoy.

I like when my car is coasting. Myh previous cars coasted even better than TL.

 

Try an Buick or any America Luxury car.

They really coast, no decceleration from engine.

 

don't worry about it. that's one of the thing to make a better mpg.

 

its not like manual tranny where u leave it in gear and let off the gas and u see the speed drop. i dont own a tl but i drive manual daily and when i drive an auto, i use breaks more often then my manaul car.

 

RandyL100

Dude, try like Davidas said ... try driving a Chevy Impala ... I had one on a business trip and man that thing will stay at 65/75 forever after you leave your foot off the gas.

I kinda like how the TL is geared with respect to the feedback on the gas pedal.. ie. you take your foot off and it slows down.

It maybe slow for some but coming form all (big) american cars its fast.

TLS RULZ

 

I like when the car coasts by itself after you stop pressing the gas pedal.

 

I may be completely deluding myself, but I like to think that my CL is just very well-built, with low friction between components. It's amazing how much better it coasts than other cars I'm used to! There's a hill I drive down every day and no matter what speed I start out at and then take my foot off the gas, it gets to 50 MPH and just stays there.

 

Me too. 'Cuz the cruise control is on.

 

try using the SS just for downshifting...then you can have engine braking that is similar to a manual transmissions...

 

It's a complex function of the ECU that, ultimately, cannot be defeated. The computer senses vehicle speed, tach, throttle position, and then decides what to do with the idle air position, and the transmission. It may or may not want to unlock the torque converter or even downshift the trans (depending on grade logic), which will affect how the car slows. Idle position will be held higher while the car is rolling than when it is stopped. This is done to give the car a "lighter" feel, and it's easier on the drivetrain.
In short, get used to it.

 

Aha, this is exactly the info I was looking for, and exactly what I was afraid of. My guess however is that it is done for emission control rather than "lighter feel". Oh well.

 

Probably not. Any time the throttle is held open, fuel is being consumed. Shutting it down would reduce both hydrocarbons, and NOx emissions. Some of the older TPI Chevy engines used to nearly shut the fuel off totally when you let up on the gas, and the torque converter stayed locked. It felt very much like a carbureted car. They did it for emissions and better fuel economy. I hated the "drag" feeling, myself.

These cars are designed to roll with little resistance. Alignment is set up this way, tight-tolerance, low friction bearings are used. Even the tires are designed for low rolling resistance. Anything to squeeze out mileage. It's a good thing, IMO. A 3500lb, 260hp car that can maintain 30mpg on a road trip is pretty impressive.

I think the overall feel may be to mimic the action of simply pushing in the clutch on a manual, when approaching the light. Engine braking action puts unnecessary strain on the drivetrain, so they use the ECU to program it out when it's not needed. Pretty genius, actually.

Todd