pressrun

I apologize upfront if this is a normal Honda/Acura feature, but this is the first of either that I've owned.

When I get off the accelorator at any speed and let the car coast, it seems like there is a slight braking affect going on? My only other comparison is a Pontiac which coasts like its going in neutral. May very well be the tranny set up, but wanted to make sure VSA or something else wasn't kicking in to slow the car down unnecessarily.

Anyone else experience this and/or know if this is just normal?

Thanks!

bradjs

i've experienced this too and wondered about it. sorry i dont have an answer though.

vtechbrain

Make sure you're driving in D. I dont have an auto but in my previous TL is was easy to shift into the lower gears inadvertently. Ive had many hondas and I wouldnt say they coast as if in neutral, though.

Xpditor

Is this on a downhill grade or all the time in the flats?

I think I remember something about a grade control. (Or was that the Toureg?) <shuffles off mumbling to himself>

rets

Sounds like the engine brake or the effects by its Drive-by-Wire Throttle System...

I thought it's quite normal to have this kind of braking effects, especially the moment you release the pedal after revving high...

SergeyM

TL has a very low (numerically high) final drive. Something like 4.4. Your Pontiac probably had something like 2.8. In other words TL is not your (grandfather's) Pontiac. Sorry could not resist. TL will also downshift when braking on down-grade.

rets

Let's say this shouldn't be related to these issues. IMO. As vtechbrain said above, yes, Honda vehicles are kind of easy to shift into the lower gears inadvertently... That's why Honda has this improved Shift Hold Control system.

Grade Logic Control System is design to improve the uphills and downhills driving. And, in order to activate Shift Hold control, the brake is the trigger. (Just like Hummer, if you have one wheel hung in the air, you have to use the special techniq to step on brake and make power direct to other wheels... ??)



Acura says:

When in automatic mode, the transmission incorporates an advanced Grade Logic Control System and Shift Hold control, which work to reduce gear "hunting" and unnecessary shifting.

To cut down on unnecessary shifting when negotiating winding roads, the Sequential SportShift automatic incorporates improved logic called Shift-Hold Control. When the throttle is suddenly released and the brakes are applied, as is the case when decelerating at the entrance of a corner, Shift-Hold Control keeps the transmission in its current (lower) ratio as it negotiates the corner and accelerates out. This feature leaves the chassis undisturbed by excess shifting, and ensures that abundant power is available without a downshift at the exit of the corner.




The 5-speed automatic alters its shift schedule when traveling uphill or downhill to reduce shift frequency, and improve speed control. Throttle position, vehicle speed and acceleration/deceleration are continuously measured, then compared with a map stored in the transmission computer. The Grade Logic Control System then determines when the car is on a hill and automatically adjusts the shift schedule to hold the engine in a lower gear for better climbing power or increased downhill engine braking.

BlackSunshine

I don't have a "D", I only have 1 2 3 4 5 6 R.

Is that an option?

j/k... noticed some auto cruising adjustments here.

inky

Grade logic. I hate it.

SergeyM

In any case it is very easy to get used to this behavior. I was annoyed at first (came from 98 Maxima) but over the time you just expect the car to break and brake less yourself. You also get used to press the gas pedal slightly to keep it moving.

vtechbrain

Actually grade logic is great especially going uphill because it avoids gear hunting. In my previous TL it worked so well I thought the damn car could "see" that the hill was ending!

pressrun

I've only experienced this on level ground...not too many hills in the Midwest!

Anyway, it really does seem like the normal operation of the tranny, but just thought I'd check and will likely get used to.

Ron A

Just came home and skimmed through this long thread. I don't think I saw anything about this in the thread, but I think the braking effect is due to the torque converter staying in lockup longer than we are used to with other cars. This has nothing to do with hills or grades. My 95 Accord V6 went in and out of lockup at 20mph, which was a pain going the last mile to my house in a 20mph zone.

I am pretty sure I am right about this, but I am also pretty sure that if I am not, someone will let me know, which is a good thing.

As pressrun said, it is the normal operation of the tranny, and you will get used to it in time.

smoore

I am glad the car doesn't pick up speed on downhill sections. There area a couple of great places in Toronto where the cops love to set up speed traps on downhill grades. The grade logic will probably save me from some tickets when I am distracted by the DVD Audio of am on the phone.

tim-in-ca

My 2002 T-Bird and 2003 PT (both auto) also loose speed when going down hill in D and it will start immediately after you take your foot off the gas. If you want to coast, just shift into Neutral ... gravity will take over and you will pick up speed, when you reach the desired speed, shift into D again ... you will start to slow down once more. This is probably due to engine braking and the transmission.

chewi

don't shift into N and shift back in to D if your are in Motion....
the gears will grind....
Trust me I've done this by accident on my 2000 TL...
It sounded bad....
But I've done this to My Benz 1990 300E and there is no grind at all.....
I guess this is ok for certain cars with auto trans.......

rets

If you shift from D to N, the sound and RPM of the engine are always going up quickly and loudly... I'm not sure if 04TL has this kind of grind of 00TL... anyone tried it yet?

gwhutch

New TL owner (05 5AT w/ Navi) and newbie poster (1st), so please bear with me.

Driving the TL on curvy roads and in town has proven tedious with the AT constant;y upshifting and downshifting unexpectedly. I have gained control by using the Sport Shift. Couple of questions however:

1. Will this Grade Logic Control System or Shift-Hold Control disable itself on slippery roads (rainy/snowy/icey)? I can see getting out-of-control quickly with this system. Especially downhill when a smooth deceleration is most important.

2. Using the Sport Shift, I downshift entering turns and approaching stops and virtually don't use the brakes. As new brakes are far cheaper than a new transmission, will all the downshifting and the on-board control systems cause pre-mature failure of the AT?

Thanks for your anticipated responses.

Actuary

if its on flat, it must be lock up clutch.

6spMike

I had a buddy that had a '95 Pontiac Grand Prix Auto.
When you take your foot off the gas, the RPM would drop quite a bit, like the converter wasn't locked up at all. I think that was normal for that car. I haven't had or seen any other auto that worked quite like that.
I have a 6MT TL, but I'm guessing the 5AT version keeps the converter locked up, so the car slows down due to engine braking.
The grade logic is a different feature that downshifts the auto for you when coasting downhill, so you won't have to use the brakes as much, if I understand it correctly.
Mike