SC a bit jerky when downshifting to a stop

[Superfly_M3]

Originally Posted by Mr.MichaelM3

I ALWAYS drive in manual mode. Only the wifey drives it in full auto. However she does not know about the charger yet

haha, I bet she'll be in for a surprise when she needs to merge fast onto a highway. Imagine, DCT drops to 6k as she is punching it, all of a sudden she's holding on for dear life, going sideways. .... haha, "somebody gonna get hurt real bad".

[Chriskm3]

Originally Posted by Mr.MichaelM3

I got the same thing! I have a vt-1 550 kit. Just installed a week ago. During the first 10 cold starts it was idling like a banshee. I believe this is normal. Also I do feel like the car is about to stall almost everytime i come to a stop. It almost hesitates. I have no doubt in the shop that installed since they've installed easily over 50 kits? (give or take). Now I've put another 100+ miles on it and it's working almost better every day.

Humm. Thats not normal.

[gamedna]

Originally Posted by Jbook

Hey all, I have the ESS 625 kit and noticed the car gives a bit of a jerk when downshifting into 2nd while slowing down (DCT). It doesn't necessarily feel like something is wrong, but it definitely isn't smooth like my upshifts and downshifts when speeding up. So far this is my only complaint with the kit other than one random stall which threw no error codes and was fine after a restart.

Has anyone else had the same experience and is it normal?

Thanks in advance!

Dame! I have 625 just install few weeks ago and got exactly the same situation. When cold start, the idle is very unstable and the car just rev itself, sometime it even stall if you drive it while the engine is cold!
I hope it will get better after I put few more miles in it!

[j2m]

Originally Posted by gamedna

Dame! I have 625 just install few weeks ago and got exactly the same situation. When cold start, the idle is very unstable and the car just rev itself, sometime it even stall if you drive it while the engine is cold!
I hope it will get better after I put few more miles in it!

Put some miles on it and make sure you are using good petrol

There are 2 circumstances I have found that create erratic idling, at least for me:
1. When it's sub -20 degrees, I will get some rough idling for a couple min's until the car has a chance to warm up a bit
2. When I use 94 octane from "Husky" (containing 10% ethanol) and for the most part my car does not like that gas and the idle will surge quite often. Same thing happened when I pumped it in my FBO 335.
I normally use 94 octane from "Petro Canada" which contains no ethanol and I find my car runs great, without the erratic idling.

[Tuner1]

Originally Posted by j2m

2. When I use 94 octane from "Husky" (containing 10% ethanol) and for the most part my car does not like that gas and the idle will surge quite often. Same thing happened when I pumped it in my FBO 335.
I normally use 94 octane from "Petro Canada" which contains no ethanol and I find my car runs great, without the erratic idling.

I wish!

Does Ultra 94 contain ethanol? Does Petro-Canada still offer an ethanol-free gasoline?
Ultra 94 contains ethanol. Due to the fact that various fuel grades are blended at the point of sale, most grades of Petro-Canada fuel may now contain up to 10% ethanol. This represents a change from the previous state, where premium fuel was ethanol-free at Petro-Canada.

FWIW my SC'd DCT M3 does the same thing.

[Chriskm3]

Originally Posted by Superfly_M3

haha, I bet she'll be in for a surprise when she needs to merge fast onto a highway. Imagine, DCT drops to 6k as she is punching it, all of a sudden she's holding on for dear life, going sideways. .... haha, "somebody gonna get hurt real bad".

Speak from experience?

[Digitalwok]

Rehashing some an older thread as I am a new SC owner and experiencing similar issues but not exactly the same. The good news and that mine does not sound as bad.

After reading this thread, I am more at ease to the fact that I did not break my car by doing a self install. Like the OP, everything works great except for coming to a stop in traffic. I had it stall on me 2 times over the past week while in auto mode. Mostly, its just rough idle as I slow and DTC still on 2nd gear. Once I am stopped and its recovered which it does quickly the car idles steady at around 700RPM.

Let hope for the best over the next few hundred miles.

[Longboarder]

Originally Posted by Digitalwok

Rehashing some an older thread as I am a new SC owner and experiencing similar issues but not exactly the same. The good news and that mine does not sound as bad.

After reading this thread, I am more at ease to the fact that I did not break my car by doing a self install. Like the OP, everything works great except for coming to a stop in traffic. I had it stall on me 2 times over the past week while in auto mode. Mostly, its just rough idle as I slow and DTC still on 2nd gear. Once I am stopped and its recovered which it does quickly the car idles steady at around 700RPM.

Let hope for the best over the next few hundred miles.

It should never stall, even with the SC. Something's up.

[Digitalwok]

Originally Posted by Longboarder

It should never stall, even with the SC. Something's up.

Tell me about it....every time I come to a stop in traffic I think...is it going to stall? Once the car comes to a complete stop everything is fine. Also, when I slow at a steady rate everything is fine. It is very reminiscent of forgetting to depress the clutch and stalling the engine.

The only things that I installed are 625, GTS DCT and replaced plugs. If the ECU does correct itself over the next few weeks I am going to remove the GTS DCT. Or should I just do it now? Thoughts?

[T!m3]

Auto (pregnant) mode on m3? Never!

[Longboarder]

Originally Posted by Digitalwok

Tell me about it....every time I come to a stop in traffic I think...is it going to stall? Once the car comes to a complete stop everything is fine. Also, when I slow at a steady rate everything is fine. It is very reminiscent of forgetting to depress the clutch and stalling the engine.

The only things that I installed are 625, GTS DCT and replaced plugs. If the ECU does correct itself over the next few weeks I am going to remove the GTS DCT. Or should I just do it now? Thoughts?

Isn't there an idle control valve on these cars that goes bad fairly regularly? I vaguely remember this being a common issue.

[Patrón]

What transmission software is most s/c folks using? I know ESS recommends the 'dct tune' but i'm curious of what most are using.

[Digitalwok]

Originally Posted by Longboarder

Isn't there an idle control valve on these cars that goes bad fairly regularly? I vaguely remember this being a common issue.

Yeah, I read about that and hoping this is not the case as I do not look forward to removing everything to change it. It could be coincidence but everything was working great before the SC. Just sharing my experience for others.

Right now, I am hoping the ECU adapts? If not my plan is to remove the GTS DCT first...then not sure how to proceed?

[Rat3d ///M]

Originally Posted by Digitalwok

Yeah, I read about that and hoping this is not the case as I do not look forward to removing everything to change it. It could be coincidence but everything was working great before the SC. Just sharing my experience for others.

Right now, I am hoping the ECU adapts? If not my plan is to remove the GTS DCT first...then not sure how to proceed?

You have to take the intake manifold off..I don't think that qualifies as "removing everything to change it". Just saying.. it's an hour long job tops.

[Digitalwok]

Originally Posted by ||||||||||

You have to take the intake manifold off..I don't think that qualifies as "removing everything to change it". Just saying.. it's an hour long job tops.

I know..being sarcastic. Just hoping that things work itself out

[81bear]

Originally Posted by Digitalwok

Rehashing some an older thread as I am a new SC owner and experiencing similar issues but not exactly the same. The good news and that mine does not sound as bad.

After reading this thread, I am more at ease to the fact that I did not break my car by doing a self install. Like the OP, everything works great except for coming to a stop in traffic. I had it stall on me 2 times over the past week while in auto mode. Mostly, its just rough idle as I slow and DTC still on 2nd gear. Once I am stopped and its recovered which it does quickly the car idles steady at around 700RPM.

Let hope for the best over the next few hundred miles.

That has never happened to me. Little bit of rough idling on initial startup first thing in the morning but that's it. Did you have your cold start programmed out with your tune? I Know speaking with AJ he said they don't recommend it as your car can stall when S/C'ed.

[81bear]

Originally Posted by Patrón

What transmission software is most s/c folks using? I know ESS recommends the 'dct tune' but i'm curious of what most are using.

GTS tune supplied remotely by Alex.