Low-end stumbling problems after Unitronic Stage1 upgrade on GSW 1.8T

[tlovejr]

Final note, (sorry for the string of posts) - I do not have this problem with the JB4. The car kicks-ass as it should. The problem was 100% with the Unitronic Stage 1 ECU flash, not the car.

 

[Diggs24]

JB4 always FTW.

 

[mfennell]

Sounds like a manual tranny/clutch issue to me? Have you done the starting vibration reduction VCDS/OBDEleven mod? I'm typical skeptical of these mods b/c folks often have no data to substantiate that they do anything but this one seems to help with manual drivers taking off. Coils/plugs good?

I performed the test with the car moving at idle, clutch fully engaged. That's when it's super obvious. I haven't done the OBDeleven mod. The car is 3 months old.

 

[mfennell]

Final note, (sorry for the string of posts) -

Not at all. Thanks for following up. I do wish I had stumbled across this before I purchased the tune. Hopefully my experience is better than yours. I'll see about getting some data to them.

 

[tigeo]

What has Unitronic said?

 

[mfennell]

What has Unitronic said?

It's only been a couple hours.

 

[Faceman]

Google "APR IS20 limp mode" …..it's all tunes at some base level/noise/background numbers of users experiencing issues.

Perfect reason to go straight to the IS38.

 

[TwinDad]

Now to disrupt everything that everyone concluded. I had the same exact issue. At idle in gear or park it would do a stumble. It would do noticeably enough in gear that it would push against the brakes. If I had a light brake on like to just slow rolling at a stop, it would lurch the car forward. Sometimes do it as I would be pulling into a parking spot. I had to be careful and keep distance to things in front of me. Plugs and coils were all fine. Couldn't figure it out. O was on jb4 only. I'm now on a protune and the issue is gone. So it's not just because of Unitronic. I'm guessing it could have been bad gas and it just took a few tanks to clean itself out. My last tank before the protune was e30, so maybe that helped

 

[TwinDad]

As far as an APR dealer charging, they shouldn't. My dealer by me doesn't charge for it. APR pays their dealers for every flash they sell. It's not listed in the APR website that additional fees may apply as well. Plus they just plug it in and walk away. They are doing other paid work while it flashes. They just need to peek at the screen every now and then. It is bullshit that APR does not regulate this. Just one more reason why I wouldn't use them. They are just whores for money and they lost their way

 

[mfennell]

It's only been a couple hours.

Now going on day 5 (3 business) with no response at all. I sent an email separately on Friday. I think this is my last day for a clean return so I may just do that. Shame.

 

[MeltedSolid]

Hm, well at least Unitronic was fairly responsive to me at the beginning of last year, maybe they've gotten worse?

 

[hoosier1661]

Final note, (sorry for the string of posts) - I do not have this problem with the JB4. The car kicks-ass as it should. The problem was 100% with the Unitronic Stage 1 ECU flash, not the car.

Thanks for the follow up. I was within the initial 15 days as well so luckily I got a refund. I'll probably go JB4 now.

 

[mfennell]

Picked up the phone. Dustin at Unitronic wants me to revert to Stage 1 and report back. I'll be shocked if it makes a difference but I have time this evening to give it a try.

 

[tigeo]

One thing I will say about tuning, adding power at even the levels you get at Stage 1 will accentuate minor things that you won't notice stock...

 

[mfennell]

Like an idiot, I'm hoping to get this figured out.

Followup. Reverted to Stage 1. Exactly the same.

Got a solid capture with OBDeleven. RPM, Air Mass, Throttle Valve, Accelerator. The time resolution isn't the best but you can see the RPM drop, then jump 3X under nearly (as near as possible) steady accelerator position. The throttle cycles back and forth a bit too. After that, it smoothly continues to accelerate under steady throttle. It's normally not that bad.