Traffic driving dynamics

[xbbnx]

He's blaming the driver, when it is in fact due to stock calibration which prioritizes reduced emmisions instead of driveability... Just one more good reason to get a Ktuner.

How does having a jerky first gear roll affect emissions?

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[invader]

How does having a jerky first gear roll affect emissions?

1st gear is more sensitive because it is the strongest and most responsive gear. Disabling rev-hang which is meant to reduce emissions, as well as setting throttle padding to medium greatly improves driveability, especially in such delicate driving conditions.

Mine was the same way, however, after flashing a ktuner tune on it with rev-hang disabled and throttle padding set to medium, I no longer have this issue. The factory tune is pretty far off for drive ability at throttle tip in.

 

[Sgamon12]

Noticed the same thing in mine. Is this with the a/c on? I noticed that without the a/c off the jerkiness is almost 100% gone. is this normal on manual cars?

 

[neteng101]

All I can say is after the drive I had home today - I'm so glad I no longer have my 9th gen Si - even with rev hang delete, its just a total PITA in creep mode. Sounds like the 10th is just as bad or even a bit worse at creeping stop/go. But yeah, rev hang - that's some utter stupid emissions shite!

 

[xbbnx]

All I can say is after the drive I had home today - I'm so glad I no longer have my 9th gen Si - even with rev hang delete, its just a total PITA in creep mode. Sounds like the 10th is just as bad or even a bit worse at creeping stop/go. But yeah, rev hang - that's some utter stupid emissions shite!

It's really atrocious. Think about the PITA of the 9th gen and then double it, that's how bad it is. I find my self constantly trying to avoid 1st gear as much as possible and it's killing the experience for me.

 

[Vrruumm]

I don't have to deal with bumper to bumper traffic, so I really haven't had this problem. Either way I normally don't leave my car in gear when in traffic. Clutch in whenever traffic is slowing down or stopping. Only in 1st gear under 10mph. If traffic is moving at a steady pace around 10mph, then I put it in 2nd. My 98 Neon used to "buck" in 1st gear. Ever since then I usually don't leave my cars in gear. Heck I coast as much as possible for them precious MPGs.

 

[Curtman]

I never really experienced this problem. I probably use the clutch more than I should. I just get rolling then push the clutch in and coast when I'm in stop and go traffic.

 

[T_A_H]

I'd like to add that I mirror much of the discussion here.

Third standard car I've owned, second turbo.

The last turbo was similar but not quite as bad in regards to first gear surging and general jerkiness, was an A4.

I think that in this car I find myself having to ride the clutch much more than my other vehicles to get a smooth driving experience.

Oh well, clutches are meant to be used right lol

RIP clutch

 

[zroger73]

This is typical in turbo vehicles.

I'm not seeing how the turbo is to blame since it's bypassed at "parking lot speeds".

 

[Stealthy86]

I'm not seeing how the turbo is to blame since it's bypassed at "parking lot speeds".

1st gear isn't a driving gear. it's a gear to get you moving. First gear is always jerky upon pressing/releasing of the gas pedal. It's more apparent in a turbo application because you're hitting boost quickly. Unless the MFG limits boost in first gear.

 

[dmitri]

1st gear isn't a driving gear. it's a gear to get you moving. First gear is always jerky upon pressing/releasing of the gas pedal. It's more apparent in a turbo application because you're hitting boost quickly. Unless the MFG limits boost in first gear.

If we're going with the "try moving at 3 - 8 mph" idea to reproduce this problem, then it is quite far from even thinking about any sort of boost, at those speeds.

The problem appears to be directly related to how the drive-by-wire curve is configured.

I've always had this "problem" (as I understood being described in OP) in all my cars, all of which were manual NA "sporty" Hondas/Acuras, and to me it has been most noticeable when moving in reverse. I was taught from the very beginning to regulate speed when backing up by adjusting clutch more than gas, and have always done it that way without any issues. I don't see "riding the clutch" under those conditions as an issue because you're not accelerating hard at all, and you make those maneuvers quite rarely. In my experience there has never been enough finesse in throttle regulators, in any cars I ever drove, to be able to make some of the more refined maneuvers, like backing into a parking lot, work by just using the gas pedal/without regulating clutch.

 

[Stealthy86]

If we're going with the "try moving at 3 - 8 mph" idea to reproduce this problem, then it is quite far from even thinking about any sort of boost, at those speeds.

The problem appears to be directly related to how the drive-by-wire curve is configured.

I've always had this "problem" (as I understood being described in OP) in all my cars, all of which were manual NA "sporty" Hondas/Acuras, and to me it has been most noticeable when moving in reverse. I was taught from the very beginning to regulate speed when backing up by adjusting clutch more than gas, and have always done it that way without any issues. I don't see "riding the clutch" under those conditions as an issue because you're not accelerating hard at all, and you make those maneuvers quite rarely. In my experience there has never been enough finesse in throttle regulators, in any cars I ever drove, to be able to make some of the more refined maneuvers, like backing into a parking lot, work by just using the gas pedal/without regulating clutch.

Point being, it's commonplace. I'm not looking to argue with the cause. i've noticed it more pronounced on turbo applications than i have with my NA vehicles. It's a short gear, it revs faster, you're in boost even at low speeds unless it's got a boost cut in 1st and 2nd (Think MS3).

 

[Monocacy]

The Si is my first 6-speed after 30+ years with 5-speed manuals. I just assumed that a shorter 1st gear would be more torquey / jerky, and find 2nd gear much smoother when traffic is moving very slowly.

 

[xbbnx]

Point being, it's commonplace. I'm not looking to argue with the cause. i've noticed it more pronounced on turbo applications than i have with my NA vehicles. It's a short gear, it revs faster, you're in boost even at low speeds unless it's got a boost cut in 1st and 2nd (Think MS3).

I tend to agree with stealthy here. Although this is my first turbo vehicle it makes sense. Coming from a NA Si I didn't have this problem, at least not this bad. Like stealthy said 1st gear is pretty short and tends to rev pretty fast constantly putting you in and out of boost even at traffic speeds. Could probably be the cause of the jerky-ness.

 

[xbbnx]

I think that in this car I find myself having to ride the clutch much more than my other vehicles to get a smooth driving experience.

Same here. It seems like you have to really rev it hard and ride the clutch a little longer than usual in other not to stall or bug down, it's strange. Sometimes I feel like I'm learning to drive a stick all over again, I haven't quite got this one down.

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