[MONSTAR]

Hello! I've recently had some issues with my BM3 tune on my N55 M2 (2018, 13,400 miles).

I am "full bolt on" with the following: VRSF catless downpipe, VRSF 6.5" HD intercooler, VRSF charge pipes, MST Inlet v2, Turbosmart VR11 diverter valve, Dinan intake, Dinan axleback.

I am running: Bootmod3 ACN 91 Stage 1

Tune has been on since November 2020 which has been about 1,000 miles. 0 issues thus far.

The other day, when rolling into WOT, I started getting what felt like a misfire or stuttering/breaking up. I was low'ish on fuel (1/4 tank) and it was relatively old fuel (about a month since my last fill up) so I stopped on the way home and filled up. It was right next to my house so I didn't drive any more. 2 days later I had a chance to drive and experienced the same issues.

I used my lunch break today to get out onto the freeway and take some logs. I admit that I hadn't logged after flashing so I don't know how it was really running, but it felt great this entire time until now. So I also admit I am inexperienced with logging. I had my girlfriend riding passenger with my work laptop and obdii to ethernet cable hooked up. I had watched a video from about 2 years ago and the process was a lot different than what I experienced. The only way that I could figure out to create a log was by going to the dashboard and having her double click to start logging right before flooring it. We must have collected about 15 logs but when I pulled back to home, they all (but 1) said only 1 second duration

Of course of all of the logs, the only one that worked was 13 seconds and only goes to about 5800 rpms.


https://www.bootmod3.net/log?id=60f0...729b7cc12b33d8

I'm not really sure how to collect the logs correctly but I am willing to get back out there tomorrow and try again if anyone has any advice.

From my one, incomplete, log....you can see the engine speed dipping constantly and thats the stuttering that I am feeling.

I ran the codes before leaving to get logs and had:

152D08 Super knocking: Injection shutdown
152608 Super knocking cylinders 6; injection shutdown

I cleared the codes before leaving and fully intended to check again when I got home but was severely out of time. I imagine that the same 2 are back and stored so I can check tomorrow before going out again. I had no CEL.

Any advice? I am on the stock spark plugs/gap (again, with 13k miles on them). I do have some NGK 97506 on order but they won't be here until next Thursday. Running shit California 91 fuel.

[Dj_Quik]

Originally Posted by MONSTAR

Hello! I've recently had some issues with my BM3 tune on my N55 M2 (2018, 13,400 miles).

I am "full bolt on" with the following: VRSF catless downpipe, VRSF 6.5" HD intercooler, VRSF charge pipes, MST Inlet v2, Turbosmart VR11 diverter valve, Dinan intake, Dinan axleback.

I am running: Bootmod3 ACN 91 Stage 1

Tune has been on since November 2020 which has been about 1,000 miles. 0 issues thus far.

The other day, when rolling into WOT, I started getting what felt like a misfire or stuttering/breaking up. I was low'ish on fuel (1/4 tank) and it was relatively old fuel (about a month since my last fill up) so I stopped on the way home and filled up. It was right next to my house so I didn't drive any more. 2 days later I had a chance to drive and experienced the same issues.

I used my lunch break today to get out onto the freeway and take some logs. I admit that I hadn't logged after flashing so I don't know how it was really running, but it felt great this entire time until now. So I also admit I am inexperienced with logging. I had my girlfriend riding passenger with my work laptop and obdii to ethernet cable hooked up. I had watched a video from about 2 years ago and the process was a lot different than what I experienced. The only way that I could figure out to create a log was by going to the dashboard and having her double click to start logging right before flooring it. We must have collected about 15 logs but when I pulled back to home, they all (but 1) said only 1 second duration

Of course of all of the logs, the only one that worked was 13 seconds and only goes to about 5800 rpms.


https://www.bootmod3.net/log?id=60f0...729b7cc12b33d8

I'm not really sure how to collect the logs correctly but I am willing to get back out there tomorrow and try again if anyone has any advice.

From my one, incomplete, log....you can see the engine speed dipping constantly and thats the stuttering that I am feeling.

I ran the codes before leaving to get logs and had:

152D08 Super knocking: Injection shutdown
152608 Super knocking cylinders 6; injection shutdown

I cleared the codes before leaving and fully intended to check again when I got home but was severely out of time. I imagine that the same 2 are back and stored so I can check tomorrow before going out again. I had no CEL.

Any advice? I am on the stock spark plugs/gap (again, with 13k miles on them). I do have some NGK 97506 on order but they won't be here until next Thursday. Running shit California 91 fuel.

First things first. DO NOT GO WOT from here on out until this issue is fixed.

That being said. From that short log, your hpfp has just taken a complete dump. Its dipping below 1400 psi and thats when you will feel misfires. Thatbsuper knock is no bueno. Means your running super lean coz the fuel pump cannot supply any more fuel at WOT.

You will need to contact ptf and see if they can resolve the issue via software. If not, you defs need a new fuel pump. If i were you, i would just go ahead and buy an upgraded fuel pump like today. In the meantime, Dont drive it hard at all rn coz your motor could go boom boom.

[CalAcacian]

I would add the ignition correction for all cylinders for your logging. Just having the individual timing is sort of a round about way of seeing where timing is being pulled, how much timing is being pulled, and which cylinder is having timing pulled.

For example, if all cylinders had 3 degrees pulled at the same time, that would not show up on this log.

[Dj_Quik]

Originally Posted by CalAcacian

I would add the ignition correction for all cylinders for your logging. Just having the individual timing is sort of a round about way of seeing where timing is being pulled, how much timing is being pulled, and which cylinder is having timing pulled.

For example, if all cylinders had 3 degrees pulled at the same time, that would not show up on this log.

I wouldnt even advise him to log anymore coz that means going full throttle

[CalAcacian]

Originally Posted by Dj_Quik

I wouldnt even advise him to log anymore coz that means going full throttle

You're right, until the HPFP issue is fixed he should avoid that.

[MONSTAR]

Dang man I actually couldn't let this sit in my head until tomorrow and I actually just went back out.

I checked my codes:
152D08 Super knocking: Injection shutdown
152608 Super knocking cylinders 6; injection shutdown
15208 Super knocking cylinder 5; injection shutdown

cleared again
flashed to stock
went for a short drive to warm up and went full throttle (before seeing your response above Dj_Quik
got an immediate error and could barely drive
had to pull over and restart car
drove the 1 mile back home real slowly

rechecked codes:

140010 misfires, more cylinders recognized
140510 Misfiring, Cylinder 5: recognized
140001 misfires, more cylinders; injection is switched off
140501 Misfiring, Cylinder 5: injection is switched off
150502 ignition, cylinder 5: Burning time too short

[MTWO]

Maybe try logging stock tune and see how it looks. Superknock is a bad code and probably because of your fuel pressure dropping but I’m no expert on this.

[MONSTAR]

Originally Posted by MTWO

Maybe try logging stock tune and see how it looks. Superknock is a bad code and probably because of your fuel pressure dropping but I’m no expert on this.

I dont think its possible to log any more right now and Im honestly kind of scared to. I just tried a WOT pull on stock tune and got an instant code that put me into limp mode. I restarted my car at the side of the road and drove very slowly back home.

[Dj_Quik]

Bro stop logging asap. No more WOT. Or tbh dont even drive the car anymore if you dont have to. I know 2 people who have had to replace motors coz they had super knock. Super knock literally means you can melt or crack your pistons

[Dj_Quik]

You can flash to stock tune so youre not running any additional boost or aggressive timing. Thats just a bandaid but reduces your chances of super knocking. But im pretty sure your hpfp is toast and going back to stock tune wont save it. You will need to replace it. When my hpfp started to fail, i would get the dips into 1400-1500 psi even on stock tune. But the pressure was still enough to keep the misfires and lean conditions at bay. Didnt want to risk blowing my motor so went ahead and bought a dorch hpfp. Now, no matter what i throw at it (even 50% ethanol), the fuel pressure does not drop. Unfortunately, this has become a common issue when you tune the n55. Some cars have weak hpfps and yours and mine are one of em.

[MONSTAR]

Originally Posted by Dj_Quik

You can flash to stock tune so youre not running any additional boost or aggressive timing. Thats just a bandaid but reduces your chances of super knocking. But im pretty sure your hpfp is toast and going back to stock tune wont save it. You will need to replace it. When my hpfp started to fail, i would get the dips into 1400-1500 psi even on stock tune. But the pressure was still enough to keep the misfires and lean conditions at bay. Didnt want to risk blowing my motor so went ahead and bought a dorch hpfp. Now, no matter what i throw at it (even 50% ethanol), the fuel pressure does not drop. Unfortunately, this has become a common issue when you tune the n55. Some cars have weak hpfps and yours and mine are one of em.

Agreed. Definitely not going to drive....unless its incredibly conservative to a local shop for the dorch install.

Kind of an unexpected expense for a $1,700 fuel pump (not including labor) on a car with 13k miles


I guess thats the risk you take with modding

[MTWO]

Originally Posted by Dj_Quik

Bro stop logging asap. No more WOT. Or tbh dont even drive the car anymore if you dont have to. I know 2 people who have had to replace motors coz they had super knock. Super knock literally means you can melt or crack your pistons

+1 if its happened on the stock tune then you should take it into a shop to take a look. Maybe a failing HPFP or injectors

[Habbe77]

I had more or less identical codes, and talked to ptf regarding drops in fuelpressure. Turned out to be bad fuel.

A bottle of octane booster and some fresh gas sorted out that issue.

My car was sitting in the garage all winter so the fuel degraded over time.

[Happy Motoring]

Does this happen in all gears? I think I experienced this exact symptom this morning but only in 4th gear going WOT. Was going to make a post but seems we are sorta experiencing same issue.

[AWC-F87]

Bummer man! Sorry to hear that. Sounds like hpfp to me. Good news is, the dorch will allow you to run e mix

[MONSTAR]

I've reached out to see what the cost of diagnostics would be, cost of installing my spark plugs (I can do this...but if the price is reasonably I'll have it done), and cost of a dorch stage 2 install.

I also just sent an email to PTF.

I am REALLY hoping the engine is ok.

If I do upgrade to a dorch stage 2, is there any reason or scenario where I would need to upgrade the LPFP as well? I would still be running my above mods and stock turbo. The closest E station is a 16 mile round trip so I probably wouldn't be running an ethanol mix too frequently

[Dj_Quik]

Originally Posted by MONSTAR

I've reached out to see what the cost of diagnostics would be, cost of installing my spark plugs (I can do this...but if the price is reasonably I'll have it done), and cost of a dorch stage 2 install.

I also just sent an email to PTF.

I am REALLY hoping the engine is ok.

If I do upgrade to a dorch stage 2, is there any reason or scenario where I would need to upgrade the LPFP as well? I would still be running my above mods and stock turbo. The closest E station is a 16 mile round trip so I probably wouldn't be running an ethanol mix too frequently

Depends on your goals. If youre not planning on running e mix often then id say youre good with dorch stage 1. If somehow youre planning big turbo then yeah stage 2. Either way, unless you planning on running full e85, you wouldnt need that upgraded lpfp tbh. But once you get that hpfp installed, splash some 20% ethanol in there, try the other maps and youre gonna be pleasantly surprised at what the car can do when its able to reach its potential!!

[AWC-F87]

I would get the stage 2 pump. There's no disadvantage other than cost. The tune will adjust fuel flow. So might as well be future proof if you plan on keeping the car long term.

On the low pressure pump, you can't just drop a bigger pump in. You'll cook the EKP. So if you get the lpfp you need to order the evolution of speed lpfp controller. It integrates super easy. Just run a couple wires. But it's like 900 bux I think. Can't remember lol.

But like others said you should be able to run e30 with the stock lpfp.

I'm running all the above mentioned mods.

[MONSTAR]

Originally Posted by AWC-F87

I would get the stage 2 pump. There's no disadvantage other than cost. The tune will adjust fuel flow. So might as well be future proof if you plan on keeping the car long term.

On the low pressure pump, you can't just drop a bigger pump in. You'll cook the EKP. So if you get the lpfp you need to order the evolution of speed lpfp controller. It integrates super easy. Just run a couple wires. But it's like 900 bux I think. Can't remember lol.

But like others said you should be able to run e30 with the stock lpfp.

I'm running all the above mentioned mods.

Thanks! Still no response to my emails from the two local shops or PTF. I would like to get things at least looked at before dropping the $1700 on the dorch stage 2.

On the other hand, with shipping times, I'm tempted to just buy it now so my car won't be down for so long. I'm not really sure what to do, just a little lost here.

[AWC-F87]

Originally Posted by MONSTAR

Thanks! Still no response to my emails from the two local shops or PTF. I would like to get things at least looked at before dropping the $1700 on the dorch stage 2.

On the other hand, with shipping times, I'm tempted to just buy it now so my car won't be down for so long. I'm not really sure what to do, just a little lost here.

Look up JMP AutoWerkz and Bavarian Workshop. They're both in Woodland Hills area. But both do good work

[MONSTAR]

Just got this response from PTF:

Looks like a hardware issue to me. I’ve seen one other M2 N55 with similar issue, low milage.

He had his HPFP replaced and it was all good.

But before replacing parts, I would suggest to have it diagnosed. It could be many other things, injector / LPFP. Looks like HPFP, but better to have it diagnosed.

[MONSTAR]

Just got my car back and happy to report it was just the spark plugs. Once the NGK 97506's were installed and gapped to .022, there were no more misfires. HPFP target and actual matched up so it looks like no issues with the HPFP as of now.

I will eventually get that dorch stage 2 and pure stage 2 turbo, but for now I can enjoy my car on the BM3 stage 1 ACN 91 tune for a long time.