APR stage 1 surge

[mrmatto]

Anyone with this issue, please send us a support ticket. We're looking into this, but need more data points on cars / ECU / scenarios it's actually affecting. Team is on it and is already collecting data.

support@goapr.com

Thank you.

I experience this (I think) on my stage 1 low torque tune. Mid-throttle gets a surge around 3k or so, and then when you upshift and the RPMs drop, there's a power drop and a laggy or choppy feeling until the revs climb again. Not an issue at lower throttle or full throttle. I always accepted it as just a GTI quirk, but if you guys think you can fix it, that would be awesomesauce. Will submit a ticket...

 

[ucfquattroguy]

Any chance it's tied to only some ECU box codes? Stage 1 low-torque also. I do get the slight "lag" on a short shift like that, but I'd expect that to a degree. I'm not getting any choppiness in that scenario (half-throttle making some torque with an upshift at 3k or thereabouts).

The only weird thing I'll get is something like a "blink of an eye" power cut during light acceleration immediately before the 3-4 upshift (in D) when the shift is at or just above 2k rpm. Had that for the v1 low-torque as well as v2 low-torque. Could it be tied to the factory TCU calibration??

Making me wonder what gremlins exist in the v1.1 OE DP IS38 software now... . (I have turbo in-hand with no intention of changing DP)

 

[mrmatto]

I’m wondering if this issue improved for anyone when they flashed a TCU tune. I can’t even purposefully replicate the issue now that my APR TCU tune is on

 

[AsheToo]

I’m wondering if this issue improved for anyone when they flashed a TCU tune. I can’t even purposefully replicate the issue now that my APR TCU tune is on

For me, the issue did not change when I had APR flash the TCU at their HQ in Alabama, nor when I added an APR intercooler and CF intake, nor when I had the APR Stage 1 ECU re-flashed to go from low torque 91 octane to low torque 93 octane.

I had my well-respected shop (GMP Performance in Charlotte) remove both the ECU and TCU tunes about 2 weeks ago, and the driveability of the car is greatly improved. The sudden surge of torque at part-throttle acceleration between 3,000 and 4,000 RPM is gone and the throttle response is more linear with no janky surprises. I could open a ticket with APR and do stuff to help them diagnose the problem, but I don't much feel like dicking around with it. I already drove to Opelika Alabama to let them pull code from my TCU so they could ensure that their tune was compatible with my box code, and I've done all I'm gonna do to assist with their R&D. I just don't have the time or patience.

At this point, I might get a Cobb AP and go with EQT Stage 1 ECU and TCU. The ability to DIY from home and not have to drive willy-nilly all around is appealing. If the EQT tunes don't fare any better than the APR tunes, then I will only have burned up $1,000 (after re-selling the Cobb AP) and a day and a half of travel to learn that OEM driveability matters more to me than aftermarket power. That, and I have confirmed my preference for top end power with a reasonably linear throttle response vs. pavement ripping low-end torque that has a mind of its own. In fact, I'd sacrifice most of APR's low-end torque if I could keep the top-end increase.

And don't take my comments about APR as a complete bitch slap of APR. They have awesome hardware, and the ECU and TCU tunes do what they are advertised to do. It's just that there are burdens that run along with the benefits, and I'm not satisfied with that.

 

[AsheToo]

This certainly could be it beyond the "normal" surgy feeling that these smaller turbo/tuned cars can have depending on driver input.

After coming back to this when mrmattolsen posted his update, I looked again at Desslok's post of EQT's info on their tune. The problem EQT described is what I'm experiencing, and it doesn't read much different from what I posted originally, which was clearly not "the 'normal' surgy feeling..." you suspected.

My original post was: "When I accelerate in 1st, 2nd, and 3rd at any kind of a pull, but not WOT, the power delivery from idle to 3,000 RPM feels like OEM - then just past 3,000 RPM, a wall of torque suddenly causes the acceleration to surge unexpectedly..." (emphasis added),

which is not a whole lot different from EQT's statement: "this issue was most commonly noticed at part throttle operation around 3000RPM and around 40-50% throttle. Before the fix, the ECU would keep the DV open, bleeding boost and creating a feeling of lag. Then it would suddenly shut the DV and result in an odd surge of power..." (emphasis added).

My point is that you come across as if you were schooling me a bit, downplaying my concern, and not giving my issue the credit it was due. You might have been showing off a bit under the guise of being "helpful," which may have left me thinking it's "just a steep toruqe (sic) curve on a tiny turbo," and I don't have enough experience to know what's what, when in reality, it's a known issue that others have experienced with APR and EQT, and EQT fixed it. Maybe you really are trying to be helpful, but you actually come across as condescending.

 

[tigeo]

After coming back to this when mrmattolsen posted his update, I looked again at Desslok's post of EQT's info on their tune. The problem EQT described is what I'm experiencing, and it doesn't read much different from what I posted originally, which was clearly not "the 'normal' surgy feeling..." you suspected.

My original post was: "When I accelerate in 1st, 2nd, and 3rd at any kind of a pull, but not WOT, the power delivery from idle to 3,000 RPM feels like OEM - then just past 3,000 RPM, a wall of torque suddenly causes the acceleration to surge unexpectedly..." (emphasis added),

which is not a whole lot different from EQT's statement: "this issue was most commonly noticed at part throttle operation around 3000RPM and around 40-50% throttle. Before the fix, the ECU would keep the DV open, bleeding boost and creating a feeling of lag. Then it would suddenly shut the DV and result in an odd surge of power..." (emphasis added).

My point is that you come across as if you were schooling me a bit, downplaying my concern, and not giving my issue the credit it was due. You might have been showing off a bit under the guise of being "helpful," which may have left me thinking it's "just a steep toruqe (sic) curve on a tiny turbo," and I don't have enough experience to know what's what, when in reality, it's a known issue that others have experienced with APR and EQT, and EQT fixed it. Maybe you really are trying to be helpful, but you actually come across as condescending.

I was simply offering some advice/guidance from reading a lot online over the years where folks' concerns are often just the normal operation of the tune....this includes myself in the example I presented after getting my first tune and thinking things were wrong. There is so much subjectivity in these types of issues. Also keep in mind that you are the one that posted your hourly rate in an attempt to justify not wanting to work with APR on the issue which is akin to posting your salary in attempt to "flex" on everyone - a little strange. I hope the EQT tune sorts your issues which it sounds like it may.