stage 1 jerking on accelaration BM3

[mkv_ppf]

has anyone exprienced a light jerking/over throttle on accelaration and on cruise?
every 5-7 seconds theres a light jerk forward and sometimes its even on upshifts and really upsets the car

tried to see if maybe its a hardware issue with the car so switched back to stock tune and the car ran smoothly
has anyone else came across this issue?

Unfortunately the response from bm3 has been very slow

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[Mayday]

Yes, I was facing the same issue with the new version of the OTS map stage 2 91 octane (AGG) which is version 2.5 released in August 15 2023. It feels like when you driving the car the RPM jumps suddenly right? Like your hitting the gas but your not and another issue I was facing with the new version of OTS Map which is burbles. I already put the burbles (OFF) but the car still pops every second I release my foot from the gas. I contacted BM3 tbh they replied me fast through emails and I explained everything to them and they replied me to share data log through BM3 while I’m driving but I didn’t because I just reflashed the old version which is 2.4 OTS Map and problem solved.

 

[BlueStreak]

So
How do we get the older tune because I have this same throttle issue

 

[ArmenLS1]

I've logged this and sent it to PTF. I have the same issue. Have you guys driven enough after flashing? Maybe it's an adaptation thing.

 

[OldHead-MKV-Owner]

I've put 1,000 miles since I started running the multimap with some E in it the whole time. Not just observations at this point, have data. The higher the E content, the worse it is. There's one anomaly. If I run E50/51 it kind of goes away. You still see it in the data, but to a lesser extent so i guess that subtle difference is feeling or not feeling it.

Anyway. Still have a few gallons of E fuel in the tank and need to run that out and log some straight 93 on the stock tune. PTF says they need those logs with all the other ones.

Will report back if I see the surging/hesitation on 93 stock tune, st 2 ots, and the multimap looks like.

 

[kfer]

I've logged this and sent it to PTF. I have the same issue. Have you guys driven enough after flashing? Maybe it's an adaptation thing.

From these values you can only see the symptom but not the cause. I'll give my opinion and then we'll wait for the pros.

The job of the throttle valve is to regulate the boost pressure.
In this case there are 3 pressures: preTrottle-Boost, Boost Target and Manifold Pressure (MAP).
The goal would be to keep all 3 the same, which is not really possible.
The so-called boost deviation ( Target - MAP) is important: when this reaches zero or is negative, the throttle valve intervenes (closes) to avoid overboost.

In this case, in my opinion, the following happens - but be prepared, everything works as designed…
( you can check my theory if you select the following values in your log: Boost (Pre-Throttle), Boost Pressure (target), MAP, Throttle, WGDC%,Accel.Pedal )
Pre-Throttle will be significantly higher than Target and MAP, which is why the throttle should stay in the 15-20% range.
MAP Will be quite a bit below target, which is normal. And WGDC should be relatively high so that you can react quickly when you accelerate.
For some unknown reason (and that's the bug / the cause), the TargetBoost will be periodically slightly increased. The MAP tries to follow and very quickly reaches the new target value because of the high WGDC.
And at this point (deviation zero or minus) the throttle intervenes.
And I think the wastegate also intervenes at that very high peaks, so WDGC should fall back sharply and then rise again.

The question is, what is the target boost at that time?

 

[BlueStreak]

On my car I have noticed anything over 75mph it’s not there. Anything lower in any gear it surges. I’m on stage 2 multi map 93oct.

 

[D3ad_Hand]

Just to confirm that this is a map issue I will report back in a week or so. I'm getting my ECU unlocked this Saturday with Femto. Going with Bm3 Stage 2 ots map. My current setup is MST V2 intake, catless Dp, and I cut off the catalyzer of the stock exhaust so it's straight piped.

 

[Daemon]

I got my ECU back and tuned Friday and noticed the same thing after filling up and hitting E35.

It also seems like burble settings aren't changing anything. Aggression 0 and 12 sound the same on both OEM and Custom modes

 

[kingdooksdb]

Manual Supra here and I’m convinced now my turbo blew because of this AGG map…. Going to remap it to 93 octane and call it a day

 

[OldHead-MKV-Owner]

I'm on a custom tune now but if anyone is having hesitation/surging issues on the OTS multimap, male sure to download the newest one, 1.2. It fixed all my drivability issues.

 

[Daemon]

I'm on a custom tune now but if anyone is having hesitation/surging issues on the OTS multimap, male sure to download the newest one, 1.2. It fixed all my drivability issues.

That's the version I'm having an issue with. When cruising it feels like the throttle is blipping ~1-2% every 5 seconds.

 

[OldHead-MKV-Owner]

Damn, I had it the other way around. Do you still have the old map? If not, ask PTF for it. Explain the issue.

 

[OldHead-MKV-Owner]

2 or 6 port?

 

[Daemon]

2 or 6 port?

'22 so 6 port. I just got the BM3+flex fuel kit set up on Friday so 1.2 is all I've got. I didn't realize I'd be able to get the old version from them though, sounds like it's worth a shot.

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