Low Speeds Gear Change to 1st

[Ozzay]

Driving in London is a pain with all the bumps everywhere even on main roads.

When I slow down over a bump I notice the car goes to 1st (am not stopping completely).

I would like it to hold 2nd. I notice it only holds 2nd on the auto if the brake is lightly applied and speed is a little bit higher than 10. I would expect 2nd to be held while the car is still somewhat rolling as when your coming out of these bumps you are going to into 1st again and its not a smooth ride its quite annoying.

The bumps in my area are not the easy type some of them really need to be slowed down for unless you don't care about the suspension or driving a much bigger car.

[Linas.P]

There isn't much you can do, no way to force the car stay in 2nd. Bumps are annoying and I wish for them to be outlawed (wishful thinking - will never happen).

[Ozzay]

13 minutes ago, Linas.P said:

There isn't much you can do, no way to force the car stay in 2nd. Bumps are annoying and I wish for them to be outlawed (wishful thinking - will never happen).

So I take it we all have this same experience.

[Linas.P]

I just don't brake for bump, but I appreciate that some bump could destroy the car.

[is200 Newbie]

Try it in sport mode - sport mode holds the revs higher for longer so COULD? hold it in 2nd gear longer?

[Linas.P]

46 minutes ago, is200 Newbie said:

Try it in sport mode - sport mode holds the revs higher for longer so COULD? hold it in 2nd gear longer?

Sport would help hold gears longer mostly when accelerating, not when braking - i.e. it will always keeps lower gear for given situation, not higher gear like would be required here. Under 10MPH I am pretty sure car downshifts to 1st... Not sure if it is good or bad, but that is what it does.

[NemesisUK]

Do you have a manual shift option?

[Ozzay]

Yeah its triptronic but its a "safe" version. Will downshift itself and never hold in second gear.

The car performs much better when warm but does not look like we can do anything. Its Londons situation for you. I see everyone else flying over bumps but they don't give a crap (scraping front bumpers).

Linas is right the sports mode doesn't exactly hold it when braking. If the majority of you have the same issue then I suppose its fine. I just wonder if other cars with autoboxes work similar (torque convertrs and dual clutch's). Even 10 mph is a bit too much for some bumps its ridiculous they really make the car jump. The UK goverment really needs to get rid of every bump and start introducing something better.

I bought a MAF sensor cleaner (unrelated to this) as I just want to see if it does improve anything (even though the cars OK).

[chr15gb]

I fine ensuring the ECT PWR is turned off makes for a much smoother take off when going over speed bumps.

You could always use the Snow mode which should lock out 1st.

[Linas.P]

1 hour ago, chr15gb said:

I fine ensuring the ECT PWR is turned off makes for a much smoother take off when going over speed bumps.

You could always use the Snow mode which should lock out 1st.

This may actually work, but it makes throttle response very numb.

1 hour ago, Ozzay said:

The UK goverment really needs to get rid of every bump and start introducing something better.

Yes they are absolutely unacceptable. I understand them in supermarket parking where speed limit suppose to be 5MPH, but on main roads they must be illegal to fit. It is absolutely retarded solution for the times... to be fair I am bigger fan of speed cameras than I am of speed bumps... at least with speed camera you are ok as long as you keeping to speed limit, on bump you never okey... and what is worse - there are not bloody standards for them either - so one bump may be just "painted over" the road and next one may rip your wheels out at 5MPH.

It is now widely accepted fact that speed bumps kills more people than they save...

But government does not care about motorists, so sadly solution isn't coming.

[Ozzay]

Tried that. It does make throttle response a bit more calm but does not hold 2nd. Even when turning corners and slowing down sometimes I wish it would stay 2nd but TBH maybe I am just being overly dramatic here.

[Ozzay]

I wonder how the other cars behave I might try and see my mates E class and see how the gears shift through.

[Linas.P]

Some cars with sequential shifting autos actually holds the gears, especially if you put them in "S" mode and only downshift if there is risk of stalling. That is what my RC does as well. But on IS250 the selector works as "limit" and not actually locks the gear.

[Mr Vlad]

Going over speed bumps in 1st is quite normal. The is250 doesn't really like ultra slow speeds other than in 1st gear. If it were to be in 2nd then the car would probably judder a bit. Even tho it's a V6 treat it like a 2 stroke motorbike and it'll love you. Just get it out of your system wanting to be in 2nd gear over bumps and just enjoy your car. 

[johnbiker7]

Hi All, 

are we not missing the point here. Speed humps are there for a purpose they make us stick to the speed limit, by making it very uncomfortable to go over them. It is the same when people complain about being caught speeding. The answer is in the drivers hands, or should I say right foot. We all like to drive fast, it's one of the pleasures of driving. If there was no deterrent the idiots out there, and we have all seen them ,would drive at any speed they feel like. Lets not forget people, a car in the wrong hands is a lethal weapon. I don't like speed humps at all, but they make me keep my speed down, and the only speed effective speed cameras are the type that register average speed, I don't like them either! 

[NemesisUK]

The trouble with many speed humps is they are too aggressive and do not comply with the strict regulations on their size/shape etc..

[Ozzay]

38 minutes ago, johnbiker7 said:

Hi All, 

are we not missing the point here. Speed humps are there for a purpose they make us stick to the speed limit, by making it very uncomfortable to go over them. It is the same when people complain about being caught speeding. The answer is in the drivers hands, or should I say right foot. We all like to drive fast, it's one of the pleasures of driving. If there was no deterrent the idiots out there, and we have all seen them ,would drive at any speed they feel like. Lets not forget people, a car in the wrong hands is a lethal weapon. I don't like speed humps at all, but they make me keep my speed down, and the only speed effective speed cameras are the type that register average speed, I don't like them either! 

No ones missing the point. I am up for slowing down. I just prefer the car to stay in 2nd if it can as it means it can roll away much nicer rather than going to 1st because you always get that jerky feeling of it quickly shifting back into 2nd. When you stay in 2nd its just much better. I am talking about the speed bumps laid across the road not the square type, the proper humping ones. Maybe I am over thinking this. Can't go anywhere in my area without it being a very slow ride.

Others around just fly through them as they don't care about anything.

[Mr Vlad]

Ahh so you say you don't like the 'jerk' from 1st to 2nd. Does it jerk when you set off normally and no speed bumps in sight just a clean get away through the gears?

[Linas.P]

yeah - I guess if I am right on where Vlad is leading... IS250 gearbox is generally smooth, so maybe you need to look into why it get's jerky in the first place.

Although, what one considers jerky, the other could consider smooth. As well, I appreciate that if slow down very shortly and then accelerate exactly at the time  when gearbox is changing from 2nd to 1st, then it could be jerky i.e. you asking gearbox to change 2nd to 1st and back to 2nd again in very quick succession and it may not be as smooth as normal, just kind of inevitable I guess.

[Mr Vlad]

As above. Couldn't put it better myself. 

[Mr Vlad]

Just for info. Took my car to asda to do a bit of a shop and get fuel. My local asda has awful speed humps. I thought to myself ok I'll go a little faster so I'm in 2nd gear. Nooooooooooo it's ruddy AWFUL. 1st gear ALL the time over those severe humps.

[Amerikan Toyota]

Same thoughts here about the tranny on my IS250. When cold a bit jerky, when warmed up smoother. Sometimes when warm, shift from 5 to 6 can sometimes be lumpy, but not always. Not the smoothest gearbox imho, but i hope its ok. 

[Linas.P]

36 minutes ago, Amerikan Toyota said:

Same thoughts here about the tranny on my IS250. When cold a bit jerky, when warmed up smoother. Sometimes when warm, shift from 5 to 6 can sometimes be lumpy, but not always. Not the smoothest gearbox imho, but i hope its ok. 

What is the mileage? Has fluid been changed or at least refreshed?

That it becomes smoother when it warms-up I guess it is just physics and as well it takes longer for gearbox to warm-up then it takes for an engine.

The second issue - lumpy when shifting from 5th to 6th is not normal, lower gears (1,2 and 3) under acceleration could punch you a bit especially when gearbox "undecided on which gear to choose", but changes between 4th, 5th and 6th should not be noticeable at all. What I mean "undecided" is that say you cruising along and then decide overtaking, at first just half a pedal, but as you start overtaking for whatever reason you decide to press it to the floor - at first gearbox thinks "it will be enough to downshift from 4th to 3rd", but then when changing to third it realises you asking for 2nd and almost changes another gear without 3rd being fully engaged.

In short anytime that you change "parameters" like accelerator input or load in between gears changing there could be a jerk as gearbox has to change what it is doing midway, but this in my experience only ever happens on 1st, 2nd and 3rd.

[Amerikan Toyota]

3 hours ago, Linas.P said:

What is the mileage? Has fluid been changed or at least refreshed?

That it becomes smoother when it warms-up I guess it is just physics and as well it takes longer for gearbox to warm-up then it takes for an engine.

The second issue - lumpy when shifting from 5th to 6th is not normal, lower gears (1,2 and 3) under acceleration could punch you a bit especially when gearbox "undecided on which gear to choose", but changes between 4th, 5th and 6th should not be noticeable at all. What I mean "undecided" is that say you cruising along and then decide overtaking, at first just half a pedal, but as you start overtaking for whatever reason you decide to press it to the floor - at first gearbox thinks "it will be enough to downshift from 4th to 3rd", but then when changing to third it realises you asking for 2nd and almost changes another gear without 3rd being fully engaged.

In short anytime that you change "parameters" like accelerator input or load in between gears changing there could be a jerk as gearbox has to change what it is doing midway, but this in my experience only ever happens on 1st, 2nd and 3rd.

This lumpy 5 to 6 usually when cold, i e the first change of the day. Now when temperatures here in Finland are not russian hell style anymore the box is much smoother from start. I bought the car in november last year. Its been a cold winter.

 

Oil has been drain/fill once, and the stuff that came out was good, no smell/colour off. Car has 112k miles. I might have some bad bushings in the drivetrain as well, ill check when i have time. 

[Linas.P]

Well, yes I guess winter is not equal winter and if it was -30C all night then I don't have much experience with that and cannot advise. Certainly when the car us "up-to temp" there should be no lumpy gear changes between 5th and 6th.