transmission
Rookie
Joined: Oct 2009
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From: MD
This has happened to me two or three times as well. I was mildly surprised the first time it happened, but after I thought about it a bit I came to the exact same conclusion as primecut above...
Prior to the F I primarily drove manual transmissions. One thing I loved about driving a manual, especially around town where you can't exactly reach extremely high speeds, was WOT thought first and second gears, then smoothly shifting right to fifth. Afraid I would miss that too much I almost made the mistake of buying a 335 instead of the F to keep my manual trans.
The few times this has happened to me, the engine might have still been a little cold (not "2 or 3 bars" on temp yet for sure as I was always still relatively close to work/home) but it was definitely not cold outside (summer) and I was driving in D, not in sport mode, and mimic'ing the manual behavior above in terms of throttle - hard on the throttle give or take winding out 2nd gear and then basically coast. I kinda knew it wouldn't just shift to 8, but hoped the transmission would figure out I went to complete idle on the throttle a little faster and upshift through a a few gears before burning off 10+mph as the rpms wind down. The behavior does make it a bit uncomfortable as you are now effectively in a "downshift" like mode right after full throttle... I found a small blip of the throttle seemed to kick it along when it happened again, although that could be coincidence
For what it's worth, the Acura TL my wife had did the same thing when driven similarly.
Thinking about some track or maybe autocross situations, I could see the logic in keeping the gear, although assuming the behavior is intentional maybe that should be saved for sport mode
Prior to the F I primarily drove manual transmissions. One thing I loved about driving a manual, especially around town where you can't exactly reach extremely high speeds, was WOT thought first and second gears, then smoothly shifting right to fifth. Afraid I would miss that too much I almost made the mistake of buying a 335 instead of the F to keep my manual trans.
The few times this has happened to me, the engine might have still been a little cold (not "2 or 3 bars" on temp yet for sure as I was always still relatively close to work/home) but it was definitely not cold outside (summer) and I was driving in D, not in sport mode, and mimic'ing the manual behavior above in terms of throttle - hard on the throttle give or take winding out 2nd gear and then basically coast. I kinda knew it wouldn't just shift to 8, but hoped the transmission would figure out I went to complete idle on the throttle a little faster and upshift through a a few gears before burning off 10+mph as the rpms wind down. The behavior does make it a bit uncomfortable as you are now effectively in a "downshift" like mode right after full throttle... I found a small blip of the throttle seemed to kick it along when it happened again, although that could be coincidence
For what it's worth, the Acura TL my wife had did the same thing when driven similarly.
Thinking about some track or maybe autocross situations, I could see the logic in keeping the gear, although assuming the behavior is intentional maybe that should be saved for sport mode
Rookie
Joined: Oct 2009
Posts: 65
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From: MD
One more thought, in the "Things that make you go hmmmm... " category 
Everyone is claiming this only happens in 2nd gear. Not that it's happened to me in other gears, but I bet few if any of us has put the car in similar circumstances in 1st or 3rd... I mean, has anybody gone WOT through first to ~redline and then coasted? That would be awkward IMO. I don't remember top speed in 3rd offhand, but I suspect most of us don't have all that many opportunities to wind out third, and when/if you do would you go ~idle then? I'm also not sure that if it did the same in third it would be as obvious because of the longer gear. (First would be very obvious) End of second just seems to "fit" to create it IMO
Everyone is claiming this only happens in 2nd gear. Not that it's happened to me in other gears, but I bet few if any of us has put the car in similar circumstances in 1st or 3rd... I mean, has anybody gone WOT through first to ~redline and then coasted? That would be awkward IMO. I don't remember top speed in 3rd offhand, but I suspect most of us don't have all that many opportunities to wind out third, and when/if you do would you go ~idle then? I'm also not sure that if it did the same in third it would be as obvious because of the longer gear. (First would be very obvious) End of second just seems to "fit" to create it IMO
OK, but anyone winding their engine to anything more than 3k rpm before the second bar is visible is asking for disaster and an early rebuild on the engine. Be nice to a cold engine and transmission - neither will like high rpm even if it's at light load.
Lexus Test Driver
Joined: Oct 2008
Posts: 1,099
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From: FL-561,352
This thread seems to be discussing several issues; one with the transmission doing what it's supposed to (holding the gear @ high revs);
then there is
That is the only time i see TRAC mentioned.
I have not experienced any of the "issues" in this thread except the normal transmission gear holding, and ONE time on a cold day i started the car, got a few blocks away, came to a stop and noticed it didn't drop into 2nd.. only into 1st (was in full auto mode). I proceeded and the car shifted from 2nd, 3rd.. and so on, and that was the only time i've ever seen that.
then there is
I have seen the same problem arise, and it is usually following an engagement of the Trac system. Vehicle will shift to second gear and refuse to move. As I am best aware there is NO ECU flash update to rectify this issue.
I have not experienced any of the "issues" in this thread except the normal transmission gear holding, and ONE time on a cold day i started the car, got a few blocks away, came to a stop and noticed it didn't drop into 2nd.. only into 1st (was in full auto mode). I proceeded and the car shifted from 2nd, 3rd.. and so on, and that was the only time i've ever seen that.
So let's see what Lexus says in the 2008 IS-F New Car Features...
So some of these complaints are aimed at the design, not the execution.
The only thing my gearbox does that annoys me is when I leave my house, go down a short hill, stop, then down another gradual downhill at 25 mph, it will refuse to upshift and revs to about 2500 rpm. If I speed up to 32 mph, it shifts up and stops annoying me. There is practically no load on the drivetrain because I'm going down a hill steep enough to coast at more than 25 mph. So I get why it doesn't immediately upshift when it's cold. It's waiting to build a little heat.
FWIW, the New Car Features document for the transmission and transmission control is a 62 page PDF. Lots of information there.
2nd Gear Start-off and Stop Control - When the engine idle speed is high while the engine is warming up and when the road surface is slippery, 2nd gear start-off and stop control for low-friction roads is automatically used in order to enhance control of drive force using the accelerator.
- When the VDIM (Vehicle Dynamics Integrated Management) system determines that the road surface is slippery from information such as an indication of a slipping tire, the power management system selects 2nd gear for starting off and stopping.
- If the VDIM system determines that the vehicle is not on a low-friction road surface, or the engine has finished warming up, 1st gear will once again be used for starting off and stopping as normal.
- When the shift lever is in the M position, 1st gear (M1) would usually be selected for starting off and stopping. However, when this control is performed, 2nd gear (M2) will automatically be selected.
- When the VDIM (Vehicle Dynamics Integrated Management) system determines that the road surface is slippery from information such as an indication of a slipping tire, the power management system selects 2nd gear for starting off and stopping.
- If the VDIM system determines that the vehicle is not on a low-friction road surface, or the engine has finished warming up, 1st gear will once again be used for starting off and stopping as normal.
- When the shift lever is in the M position, 1st gear (M1) would usually be selected for starting off and stopping. However, when this control is performed, 2nd gear (M2) will automatically be selected.
Examples of Control (Only when engine is warming up)
TRAC operates when the vehicle starts off.
If TRAC operates when the vehicle starts off in 1st gear, the gear will be changed to 2nd immediately to reduce driving force transmitted to the tires.
ABS operates before the vehicle stops.
If ABS operates before the vehicle stops, the transmission only shifts down to 2nd gear. Even after the vehicle stops, 2nd gear is maintained. In this case, 2nd gear will be used when the vehicle starts off.
TRAC operates when the vehicle starts off.
If TRAC operates when the vehicle starts off in 1st gear, the gear will be changed to 2nd immediately to reduce driving force transmitted to the tires.
ABS operates before the vehicle stops.
If ABS operates before the vehicle stops, the transmission only shifts down to 2nd gear. Even after the vehicle stops, 2nd gear is maintained. In this case, 2nd gear will be used when the vehicle starts off.
The only thing my gearbox does that annoys me is when I leave my house, go down a short hill, stop, then down another gradual downhill at 25 mph, it will refuse to upshift and revs to about 2500 rpm. If I speed up to 32 mph, it shifts up and stops annoying me. There is practically no load on the drivetrain because I'm going down a hill steep enough to coast at more than 25 mph. So I get why it doesn't immediately upshift when it's cold. It's waiting to build a little heat.
FWIW, the New Car Features document for the transmission and transmission control is a 62 page PDF. Lots of information there.
Lexus Fanatic
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Joined: Nov 2004
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From: Under an IS F since 2008
So some of these complaints are aimed at the design, not the execution.
The only thing my gearbox does that annoys me is when I leave my house, go down a short hill, stop, then down another gradual downhill at 25 mph, it will refuse to upshift and revs to about 2500 rpm. If I speed up to 32 mph, it shifts up and stops annoying me. There is practically no load on the drivetrain because I'm going down a hill steep enough to coast at more than 25 mph. So I get why it doesn't immediately upshift when it's cold. It's waiting to build a little heat.
The only thing my gearbox does that annoys me is when I leave my house, go down a short hill, stop, then down another gradual downhill at 25 mph, it will refuse to upshift and revs to about 2500 rpm. If I speed up to 32 mph, it shifts up and stops annoying me. There is practically no load on the drivetrain because I'm going down a hill steep enough to coast at more than 25 mph. So I get why it doesn't immediately upshift when it's cold. It's waiting to build a little heat.
I also noticed the same things on declines as well.
Joe Z
Lexus Test Driver
Joined: Oct 2008
Posts: 1,099
Likes: 0
From: FL-561,352
So, as luck would have it.. my transmission started "behaving strangely" this morning on my way to work. Car was starting from 2nd gear for no "apparent" reason...
http://www.youtube.com/watch?v=bAVcJ7tKrS8
http://www.youtube.com/watch?v=bAVcJ7tKrS8
VDIM has a mind of its own. Must have thought it was slippery out - the engine was still pretty cold - only one bar on the oil temp. Still, with 73 ambient temp, I wouldn't expect a second gear start either.
Lexus Test Driver
Joined: Oct 2008
Posts: 1,099
Likes: 0
From: FL-561,352
Yup.. that's my feeling exactly (temperature = normal). The engine was cold - parked over night, but I think our low for the evening MIGHT have been 68F.
The only thing I can think of is I get SLIGHT wheel slippage when making the first left turn out of my street (gravel), and then have about 1/10th of a mile before the stop sign where I notice the 2nd gear 'stick'...
2nd Gear Start-off and Stop Control - When the engine idle speed is high while the engine is warming up and when the road surface is slippery, 2nd gear start-off and stop control for low-friction roads is automatically used in order to enhance control of drive force using the accelerator.
Is the only potential explanation I can think of?
The only thing I can think of is I get SLIGHT wheel slippage when making the first left turn out of my street (gravel), and then have about 1/10th of a mile before the stop sign where I notice the 2nd gear 'stick'...
2nd Gear Start-off and Stop Control - When the engine idle speed is high while the engine is warming up and when the road surface is slippery, 2nd gear start-off and stop control for low-friction roads is automatically used in order to enhance control of drive force using the accelerator.
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