Throttle Response

[AlienneilA]

I posted on here awhile ago about slow startup, but ive never actually floored the car until recently, when I put it in power mode and mashed the gas. The thing is, the throtte response seemed abnormally slow, I know its not a ferrari or anything but I have the grounding kit installed on it and it seemed like it took 2 seconds before i felt any roar. The only engine mod I have is the grounding kit, no intake or anything, let me know what you all think, Ill have the dealer check it when I take it in in about 1000 miles.

[UKPulse]

You'll have to forgive my ignorance, but is your 300 the manual or the e-Shift version? We only have the e-Shift (Auto) version over here in the UK, and yes when you floor it there is a momentary lag as it kicks down. I'd imagine the manual is like any other - pretty much instant.

[ColinBarber]

If it is an e-shift then what happens when you have it set in 2nd at 20mph and then floor it? Response should be instant.

I would imagine the delay you noticed is the auto box changing down a couple of gears.

[kev dood]

from driving the IS300 in the UK I would agree that its the slow response of the box changing gear.

Gotta admit, both IS200 and IS300 have poor auto boxes, not a patch on other manufacturers. IS300 is better and also has more gears and seems smoother!

[UKPulse]

Good point - stick the e-Shift in 2nd and take off from a standing start and it's pretty much instant :)

Comparing the IS200 & IS300 Auto boxes to the Vauxhall Omega 2.6 V6 Auto, Mercedes C200 Kompressor Auto, Vauxhall Astra 1.8 Auto and Renault Megane 1.6 Auto, I'd have to say that the Lexus box is on a par with the Merc, but is light years ahead of the Vauxhall & Renault. Had the misfortune of doing 2,500 miles in 2 weeks in the Omega - now that's an auto box that sucks Lurches on every down-change as your slowing to a stop :duh:

[kev dood]

I think that Renault make about the worst auto boxes you can get!

Judging from what a friend of mine says (ex merc mechanic) some of the merc boxes are just as bad (A-class esp.)

[justin.cockett]

Merc Auto boxes have a couple if irritating features....

1. When moving off with light throttle openings they start off in second, the point at which first is selected is rather unprintable so you never feel in full control of the standing start acceleration, also they sometimes start in second, then swap to first.

2. The Merc boxes change down when slowing gently... why? Surely this must cause more wear on the box? Lexus boxes hold the gear until you have stopped avoiding unnecessary changes. The other disadvantage with the Merc system is that you feel all the down-changes and it makes the brakes harder to feather to a gentle stop, add this to the creaky merc brakes and achieving a gentle stop can be quite a challenge in a Merc. Perhaps this is why they invented “Sensotronic” brake control as a work-round......

3. There is a reliability question on some Merc auto boxes... perhaps because of all that extre gear changing?

I wonder what the new 7-speed auto will be like in some E-series models from next year?

[kev dood]

I guess changing down whilst slowing helps braking and alsso means when you start again, then box is already in correct gear so faster response.

Regarding the ctarting off in 2nd, most autos do don't they? When in Economy, it always starts in 2nd, no matter how hard you boot it. When switching to sport mode, it starts in 2nd unless you boot it enough for it to go for 1st.

I think this is ok otherwise you would not get as smooth a ride on startup if you need 1st to 2nd change.

Thing I like about autos is the kickdown. Some cars it gives a nice jump in acceleration

[ColinBarber]

both IS200 and IS300 have poor auto boxes

The IS300/GS300/GS430/LS430 have one of the best auto boxes available. Certainly one of the smoothest. The gearchange isn't as quick as some but then Lexus do not make their cars that way

[ColinBarber]

A nice box is the Toyota one which links to the Sat Nav so it downshifts as you get to the bottom of a hill or you round a corner so there is no waiting for kick down. Only available in Japan at the moment. Hopefully will be available on the next GS or LS in the UK.

[Glenn]

Don't know if this makes sense or not but I have noticed with my IS300 that it seems to learn the way you drive it. If I take it easy for a couple of days then decide to have some fun it seems a bit reluctant at first. Then after a while using E-shift mode and a heavy right foot it wakes up and springs into action.

Probably sounds strange but this is what I have found with mine.

Glenn

[Matthew_McNally]

Don't know if this makes sense or not but I have noticed with my IS300 that it seems to learn the way you drive it. If I take it easy for a couple of days then decide to have some fun it seems a bit reluctant at first. Then after a while using E-shift mode and a heavy right foot it wakes up and springs into action.

Probably sounds strange but this is what I have found with mine.

Glenn

yes - this is certainly the case with the newer models - they have an adaptive, or learning gear box, it adjusts itself to your driving style.

And I don't think anyone should complain about autoboxes until you have driven a 1.2 Vauxhall Corsa - with tiptronic auto gear box.

so jerky you have to wear a helmet as your head near bangs on the windscreen.

[justin.cockett]

Rrom the Corsa comment above.

Basic Rules of motoring.........

1. Never buy a vehicle with more wheels than seats

2. Never buy a vehicle with more gears than the engine has cylinders!

J.

[Matthew_McNally]

Rrom the Corsa comment above.

Basic Rules of motoring.........

1. Never buy a vehicle with more wheels than seats

2. Never buy a vehicle with more gears than the engine has cylinders!

J.

was in an accident - this was what my POS insurance company put me in for a week or so, until I kicked up enough of a fuss and got shut.

;) :D :D

[justin.cockett]

Rrom the Corsa comment above.

Basic Rules of motoring.........

1. Never buy a vehicle with more wheels than seats

2. Never buy a vehicle with more gears than the engine has cylinders!

J.

was in an accident - this was what my POS insurance company put me in for a week or so, until I kicked up enough of a fuss and got shut.

;) :D :D

Lexus seem to have a thing with Corsas, only the one they leant me when my car was being resprayed had a cylinder missing. there were only three!

J.

[UKPulse]

Don't know if this makes sense or not but I have noticed with my IS300 that it seems to learn the way you drive it. If I take it easy for a couple of days then decide to have some fun it seems a bit reluctant at first. Then after a while using E-shift mode and a heavy right foot it wakes up and springs into action.

Probably sounds strange but this is what I have found with mine.

Glenn

Yup, mine seems to do the same.

Every time I get the car back after the other half has borrowed it, I have a job getting it over 30mph!!

[kev dood]

The gearchange isn't as quick as some but then Lexus do not make their cars that way

Surely a "good" auto would have both? Otherwise you may as well put the smart gearbox in and wait the 2.5secs it takes to change!

Is that not why CVT's are nice and smooth to drive - cos they don't have change delays!? (they do have many other problems though!!)

All I know is, I wouldn't like the Lexus auto as its changes are too slow for my liking.

[dark_is200]

Have you had the ECU reflashed? Some of the E-Shift IS300's have old ECU software that has problems to do with slow shifting.

http://is300.net/forum/viewtopic.php?t=133...hlight=trac+ecu