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RPM hold fix?

8946 Views 17 Replies 9 Participants Last post by  Sai Xiong
I have a manual transmission and when I press the clutch in to shift the rpms first stay where they were when I pushed the clutch and slowly start to drop. This makes it hard to drive quickly smoothly. Does anyone else have this issue, and a way to get the engine to drop rpms quicker?
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Mine is the same... the flywheel in these things must be heavy as a mofo. A lightweight flywheel and performance clutch would greatly reduce the amount of rotational mass and bring the RPMs down much quicker between shifts. Honestly the throw length for the shift points is what makes this thing hard to drive smoothly, but I have had mine since 9/11 and gotten pretty used to it now.
I would say that the reason this is happening is the ECU programming. I am sure that the flywheel is not lightweight. It is a drive-by-wire system so there is no mechanical throttle cable. The ecu will hold the rpm at that level. (The way cruise and traction control work.) I am not sure why. I may want to talk to a Toyota rep about this.
Would this be from the hill assist?
From what I have read hill assist is all controlled by the ECU and the brakes. There's nothing in the transmission itself that is actually holding the car at an incline. It's all sensors and inputs to the ECU.

As for the OP's comments and mine, it's completely possible that it is not even mechanical and there is some sort of rev matching mixed into the tune on the ECU, if that's the case that would be one of the first things I wish the tuner would out on any OTS maps ... that's a "IF" any sort of tuning software for these ECUs become available.
I have a manual transmission and when I press the clutch in to shift the rpms first stay where they were when I pushed the clutch and slowly start to drop. This makes it hard to drive quickly smoothly. Does anyone else have this issue, and a way to get the engine to drop rpms quicker?
For info, mine does the same thing as well. It seems like it only happens when I'm driving a little more aggressive and shifting above 3K RPMs. I'll have to experiment a little and see.
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sorry to bring up an old thread but i was seriously just about to ask about this. i have the 6 speed and never had a car hold rpm's when shifting. my dads scion XA didn't even do it. did you guys ever figure anything out or have you just got used to it?
Just gotten used to it.
nice sounds good.
hate that rpms hold really do!
any solution to fix this?
I don't really get the issue with the rpm hold. IMO, it is better that way.
i get used to it, i always timed my shifting between gears
This is not a thing of getting use to it,this is going to bring issues faster then you know!!
ask a well trained mechanic!! theres no need for the engine to hold rpms unless equiped with a racing or sequential gearbox.
this issue will bring soon posts regarding premature clutch and drivetrain faiures.
This is a common issue with poorly designed drive by wire systems!!
heard that lotus use this same gearbox and past generation engines and guess what? they dont suffer that rpm hold issue.
some subaru and nissan models are reporting the same issue,i bet is the same DBW components manufacturer.
This is not a thing of getting use to it,this is going to bring issues faster then you know!!
ask a well trained mechanic!! theres no need for the engine to hold rpms unless equiped with a racing or sequential gearbox.
this issue will bring soon posts regarding premature clutch and drivetrain faiures.
This is a common issue with poorly designed drive by wire systems!!
heard that lotus use this same gearbox and past generation engines and guess what? they dont suffer that rpm hold issue.
some subaru and nissan models are reporting the same issue,i bet is the same DBW components manufacturer.
Correct me if I'm wrong but the lotus in older generations did not come with valvematic. It must be a design feat to have an rpm fix.

I'm sure OEM's already have a study to support this feat. There's a purpose why it is there. For me, I feel a smoother gear shift.

I'd be curious to see reports on premature clutch wear because of this. If it happens to me, I'll be happy to report it
Correct me if I'm wrong but the lotus in older generations did not come with valvematic. It must be a design feat to have an rpm fix.

I'm sure OEM's already have a study to support this feat. There's a purpose why it is there. For me, I feel a smoother gear shift.

I'd be curious to see reports on premature clutch wear because of this. If it happens to me, I'll be happy to report it
correct,not valvematic but the 2zz gearbox is the same 6 speed from matrix,corolla and celica, never said it was a valvematic,Toyota or any manufacturer will never tell,remember VW??

my IM is only 800 miles young, thats why a said that in a near future clutch or drivetrain issues will be here.
i live in an island and going uphill while shifting from 2nd to 3rd with the engine at 4000rpms is a bit harsh it will eat that clutch really fast,its not the same in straight plain terrain!!!
only reason i see is to help mantain momentum

did you notice any difference in rpms when hill assist is acitvaded???
correct,not valvematic but the 2zz gearbox is the same 6 speed from matrix,corolla and celica, never said it was a valvematic,Toyota or any manufacturer will never tell,remember VW??

my IM is only 800 miles young, thats why a said that in a near future clutch or drivetrain issues will be here.
i live in an island and going uphill while shifting from 2nd to 3rd with the engine at 4000rpms is a bit harsh it will eat that clutch really fast,its not the same in straight plain terrain!!!
only reason i see is to help mantain momentum

did you notice any difference in rpms when hill assist is acitvaded???
I see. IMO, shifting from 2nd to 3rd at 4k rpm should be fine. Even on uphill, it takes less than a second to shift.
I don't think I've driven my car over 4k lol. I keep my shift points about 2k without lugging. Uphill may be 3k. What uphill grade do you climb?

No difference in rpm with hill assist. In most cases, 1.5k rpm should move it. On really steep ones, maybe around 2k.
I see. IMO, shifting from 2nd to 3rd at 4k rpm should be fine. Even on uphill, it takes less than a second to shift.
I don't think I've driven my car over 4k lol. I keep my shift points about 2k without lugging. Uphill may be 3k. What uphill grade do you climb?

No difference in rpm with hill assist. In most cases, 1.5k rpm should move it. On really steep ones, maybe around 2k.
4k going uphill in 2nd gear is a bit forced!!
uphill here can go near 35 to 40 degrees at some point, some dont allow you to shift often so 2nd to 3rd is for cases speed and momentum is good. Same car in same situation with a CVT will be easier to drive but that CVT will be hurt sooner!! where i live maybe 60% of the roads are hills !!
thats the price of living in an island!!
Yes i know the solution!!! move to plains!!!:laugh:
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I noticed with the clutch pedal mod it eliminated the rev thing quite a bit
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