[lonewolf1911]

Looking for some input as I'm seeing my HPFP actual drop over 1k below target, logged in this 4th gear pull, WOT. I've been on BM3 OTS ST2 maps since 17k, now at 30k. Not long ago I started to notice misfires/stuttering above 5k RPM. I was thinking I had some low octane gas at first and I switched down to the 91ACN map from 91, which I typically run. This behavior remained persistent on new fuel, it appears more often with colder temps and high load.

Started logging as a result and noticed some inconsistencies, fuel pressure seems fine in the upper range but the midrange drop has me suspecting a weak factory HPFP or a possible issue with my LPFP?

I had no stutters in the attached log but the HPFP drop is clear, AFR appears to be on target in the upper range. Am I lean down low?

Wondering if anyone has dealt with a similar issue, I believe this car had a LPFP recall done that I can check into. No CELs are present. Trying to narrow this down before I pull the trigger on a new HPFP, I'd probably go with Dorch ST2 as I'm planning for more upgrades.


https://www.bootmod3.net/log?id=61ff710bd10b437c875e4ac2

2014 335I: 30k
-EWG/8SPD
-BM3 ST2: MM1-91ACN
-XHP ST3
-ER CP
-ER DP
-ER CIC
-Dinan CAI
-NGK Plugs

[thejeremyman9]

Are you running multimap? Try a normal stage 1 or stage 2 91 octane map and log that. Any codes?

For some reason your STFTs are hugely negative, which doesnt make sense for an OTS pump gas map with pump gas. multimaps have some strange behavior sometimes, so try a normal map

[Eschmacher]

I am currently having the same issue, though my crash is not nearly that bad, only down to 2000, not below.

Reached out to PTF, they said the STFT dropping below 1 when fuel pressure drops is intended. Told me to upgrade hpfp, which I was already planning to do... So I finally pulled the trigger. Probably doing the install in the next two weeks.

[lonewolf1911]

Originally Posted by thejeremyman9

Are you running multimap? Try a normal stage 1 or stage 2 91 octane map and log that. Any codes?

For some reason your STFTs are hugely negative, which doesnt make sense for an OTS pump gas map with pump gas. multimaps have some strange behavior sometimes, so try a normal map

I was running the multimap indeed, had no codes. Switched over shortly after it came out to play with anti-lag and on-the-fly switching. Starting to regret that as it seems to be directly related.

Just flashed back to the standard ST2 91 AGG map which I previously ran and took a few quick logs. Not my best, dealing with torrential rain but I'm seeing nowhere near the same HPFP dip and STFTs appear normal. I'm a bit puzzled and will likely continue with more logs. If I have no actual HW issue and others have reported similar issues it must not be an intended result from the map?

I haven't reached out to PTF yet but I'm surprised there would be such a variance. Next, I'll do some back to back logs when I can switch between the standard and multi-variant to reduce other variables.

Stage 2 91OCT AGG:
https://www.bootmod3.net/log?id=621c...0b4333683e6a56
https://www.bootmod3.net/log?id=621c...0b43355b119bc8

[lonewolf1911]

Originally Posted by Eschmacher

I am currently having the same issue, though my crash is not nearly that bad, only down to 2000, not below.

Reached out to PTF, they said the STFT dropping below 1 when fuel pressure drops is intended. Told me to upgrade hpfp, which I was already planning to do... So I finally pulled the trigger. Probably doing the install in the next two weeks.

Were you running the standard OTS ST2 multimap with just pump gas as well?

[SeanFitz335]

I am dealing with exactly the same issue right now. 2014 335i RWD as well with same symptoms. Since switching to Stage 2 multi map ACN91 I am getting sputtering at 5000+ rpm in 3rd. Logs showed the HPFP dropping to as low as 1400 on a target of 2450. AFR going as rich as 11.3:1. I thought my ethanol mix was off as I was mixing to E20 to clean up timing with my crappy AZ fuel. But, cleaned out with Chevron 91 for a couple of tanks and still had the issue.

Reached out to PTF and they asked for a 3-4 gear pull log (below). They came back with a test map and asked for more logs on the test. I provided 4 logs and they just responded yesterday saying it looks better and gave me test map 2 which I will load and log this week.

There is another thread with similar symptoms that prompted me to reach out to PTF. My guess is this is a known issue that is not a hardware issue but software driven.

https://datazap.me/u/seanfitz335/log...1-3-4-6-8-9-21

[thejeremyman9]

Originally Posted by Eschmacher

I am currently having the same issue, though my crash is not nearly that bad, only down to 2000, not below.

Reached out to PTF, they said the STFT dropping below 1 when fuel pressure drops is intended. Told me to upgrade hpfp, which I was already planning to do... So I finally pulled the trigger. Probably doing the install in the next two weeks.

You had the same issue on a pump gas map? Running pump gas and HPFP pressure crashes? HPFP upgrade is not a solution to that as there shouldnt be a hardware problem in the first place

Every log i have ever seen with a HPFP crash low enough to affect fueling the STFTs go positive. If the fuel trims went below 1 when your HPFP was already crashing the car would go extremely lean, which would not be good.

[thejeremyman9]

Originally Posted by lonewolf1911

I was running the multimap indeed, had no codes. Switched over shortly after it came out to play with anti-lag and on-the-fly switching. Starting to regret that as it seems to be directly related.

Just flashed back to the standard ST2 91 AGG map which I previously ran and took a few quick logs. Not my best, dealing with torrential rain but I'm seeing nowhere near the same HPFP dip and STFTs appear normal. I'm a bit puzzled and will likely continue with more logs. If I have no actual HW issue and others have reported similar issues it must not be an intended result from the map?

I haven't reached out to PTF yet but I'm surprised there would be such a variance. Next, I'll do some back to back logs when I can switch between the standard and multi-variant to reduce other variables.

Stage 2 91OCT AGG:
https://www.bootmod3.net/log?id=621c...0b4333683e6a56
https://www.bootmod3.net/log?id=621c...0b43355b119bc8

You should reach out to PTF so that they know there is a potential issue with the MM. I took a quick look at one of the new logs and STFTs are way closer to where they should be and yes little to no HPFP dip. I would not run the MM

[n55david]

Issue with it being the multimap. Some cars it freaks out on.. like mine

Can't wait to give them hell when the new stage 3 maps comes out

[lonewolf1911]

I'll reach out to PTF so they have additional feedback and data on the issue, glad it's just related to the multimap. This exact issue may not be widespread but it's concerning as this map has been out for quite some time now.

I drove on this for several months without noticing anything was amiss, mainly just commuting with some pulls here are there. I didn't log after switching as I wasn't expecting any significant difference from the standard map. Lesson learned here, considering my AFR still remained close to target should I be concerned about any damage?

I'm a bit confused seeing the HPFP dip and wondering how the ECU reacted to compensate. AFR readings resulting in the STFT value going very negative instead of positive, leading to the adjustment, rich conditions as a result? As stated it doesn't make sense, to pull fuel when the dip is present? Not super versed in this area but it makes me want to question the data being logged, specifically with the HPFP pressure, not sure.

[SoCalM235iR]

Sounds similar to my issues as described in this post.

https://f30.bimmerpost.com/forums/sh....php?t=1861375

Reset your adaptations and try it with the MAF unplugged. That's how I "fixed" the issue. Not ideal but functional and the car performs well and the logs look acceptable.

[thejeremyman9]

Originally Posted by lonewolf1911

I'll reach out to PTF so they have additional feedback and data on the issue, glad it's just related to the multimap. This exact issue may not be widespread but it's concerning as this map has been out for quite some time now.

I drove on this for several months without noticing anything was amiss, mainly just commuting with some pulls here are there. I didn't log after switching as I wasn't expecting any significant difference from the standard map. Lesson learned here, considering my AFR still remained close to target should I be concerned about any damage?

I'm a bit confused seeing the HPFP dip and wondering how the ECU reacted to compensate. AFR readings resulting in the STFT value going very negative instead of positive, leading to the adjustment, rich conditions as a result? As stated it doesn't make sense, to pull fuel when the dip is present? Not super versed in this area but it makes me want to question the data being logged, specifically with the HPFP pressure, not sure.

I dont see AFR target in the logs but my guess is that the fueling is off so the car is running rich, causing the HPFP crash (its supplying more fuel than needed and HPFP can't keep up). As a result of being rich, STFTs are negative as seen in the first log. The rich condition is the cause not the effect. Negative STFTs and HPFP dip both lead to lean conditions, not rich.

The DME will not pull fuel in response to HPFP crash. If the HPFP pressure dips low enough to reduce the fuel supply, AFR will go lean, and STFTs will increase (positive).

In the datalog your HPFP angle is 109 during the crash, which supposedly means the pump "duty cycle" is maxed.

[thejeremyman9]

Originally Posted by SoCalE90

Sounds similar to my issues as described in this post.

https://f30.bimmerpost.com/forums/sh....php?t=1861375

Reset your adaptations and try it with the MAF unplugged. That's how I "fixed" the issue. Not ideal but functional and the car performs well and the logs look acceptable.

All he had to do was switch off the multimap. Your issue was different from what i recall, and your positive STFTs will pushing the car rich, causing HPFP to crash.

[SoCalM235iR]

Originally Posted by thejeremyman9

All he had to do was switch off the multimap. Your issue was different from what i recall, and your positive STFTs will pushing the car rich, causing HPFP to crash.

Didn't read about the Multimaps and yes, mine was going rich.

[ericlr1225]

Originally Posted by SoCalE90

Didn't read about the Multimaps and yes, mine was going rich.

https://www.bootmod3.net/log?id=6363...90c66aae9556bf
kinda same issue running stage 1 acn91
new plugs, 0.028'' gapped, new coils
hpfp dropped like a mofo

[thejeremyman9]

Originally Posted by ericlr1225

https://www.bootmod3.net/log?id=6363...90c66aae9556bf
kinda same issue running stage 1 acn91
new plugs, 0.028'' gapped, new coils
hpfp dropped like a mofo

No ethanol? Your STFTs are quite positive, and LTFTs are not in the log, need those added.

[ericlr1225]

Originally Posted by thejeremyman9

No ethanol? Your STFTs are quite positive, and LTFTs are not in the log, need those added.

https://www.bootmod3.net/log?id=636b...90c66aae9570e4

no ethanol. Just did a short pull after seeing your reply. It's stock tune. mofo keeps crashing LOL
it seems like going into a loop hole.

a few directions I got by digging around:
1. plugs gapping. NGK fixed from 0.022'' to 0.028'' Didn't work (@F87source @ZM2)
2. EPKM fail. I don't have CEL, no engine shut off during driving, never stall, a little bit vibration during idle every couple seconds, rpm stays between 600-700rpm. afr moving between 14-15.3 back and forth. (Custom tuner wants me to buy a new EPKM)
3. HPFP. I don't think this would fail below stage 1&2 91acn power level. since my car's only 20k miles. Bought it in 2018, 4 years maintenance from dealer, all mods put on couple weeks ago. I ordered Dorch stg2 Since I'm going to do Ethanol later anyway.
4. LPFP. We(N55 M2) don't have LPFP sensor. I don't know how to diagnose it. But I don't have any trouble daily driving it for now. (from Custom tuner)
5. Bad Octane or Injector. Again, car is only 20k miles, full maintenance. Monitored with bimmerlink during driving. got 1 or 2 misfire count in different cynlinder but nothing major to throw a CEL from ECU. Sent one log to BM3 support after having a superknock during stage 2 acn91 two days ago. (Guessed by @Halim from PTF)

Crashing all happened during WOT around 3k-7k rpm

Other than that, just like you said, some of my logs looked totally fine.

[n55david]

Originally Posted by ericlr1225

https://www.bootmod3.net/log?id=636beac4c090c66aae9570e4

Just did a short pull after seeing your reply. It's stock tune. mofo keeps crashing LOL

1. I'd let it get a little warmer before beating on the car..
2. God your fuel is trash.. sorry
3. Stock tune? What specific mods are done?

[thejeremyman9]

Originally Posted by ericlr1225

https://www.bootmod3.net/log?id=636b...90c66aae9570e4

no ethanol. Just did a short pull after seeing your reply. It's stock tune. mofo keeps crashing LOL
it seems like going into a loop hole.

a few directions I got by digging around:
1. plugs gapping. NGK fixed from 0.022'' to 0.028'' Didn't work (@F87source @ZM2)
2. EPKM fail. I don't have CEL, no engine shut off during driving, never stall, a little bit vibration during idle every couple seconds, rpm stays between 600-700rpm. afr moving between 14-15.3 back and forth. (Custom tuner wants me to buy a new EPKM)
3. HPFP. I don't think this would fail below stage 1&2 91acn power level. since my car's only 20k miles. Bought it in 2018, 4 years maintenance from dealer, all mods put on couple weeks ago. I ordered Dorch stg2 Since I'm going to do Ethanol later anyway.
4. LPFP. We(N55 M2) don't have LPFP sensor. I don't know how to diagnose it. But I don't have any trouble daily driving it for now. (from Custom tuner)
5. Bad Octane or Injector. Again, car is only 20k miles, full maintenance. Monitored with bimmerlink during driving. got 1 or 2 misfire count in different cynlinder but nothing major to throw a CEL from ECU. Sent one log to BM3 support after having a superknock during stage 2 acn91 two days ago. (Guessed by @Halim from PTF)

Crashing all happened during WOT around 4k-7k rpm(stock tune) Started 3-4k rpm in Stage 1&2 tune.

Other than that, just like you said, some of my logs looked totally fine.

The car is adding a ton of fuel before the HPFP even crashes. IT wouldnt be the first time the fuel trims are actually pushing the car to add more fuel than it needs and crash HPFP. You also still don't have LTFTs in the log that i saw.

The HPFP is mechanical so it really doesn't partially fail like that. I would expect LPFP or EPKM to be an all or nothing issue, not a low fuel flow issue.

Your octane is bad but that wont affect fuel quantity.

[ericlr1225]

Originally Posted by n55david

1. I'd let it get a little warmer before beating on the car..
2. God your fuel is trash.. sorry
3. Stock tune? What specific mods are done?

CSF IC, sport cat 200cel DP, MPE, FTP CP&BP, MST Inlet, NGK plugs, Eldor coils, Turbo Smart BOV, 3.5 tmap sensor

I usually don't buy cheap mods.

[ericlr1225]

Originally Posted by thejeremyman9

The car is adding a ton of fuel before the HPFP even crashes. IT wouldnt be the first time the fuel trims are actually pushing the car to add more fuel than it needs and crash HPFP. You also still don't have LTFTs in the log that i saw.

The HPFP is mechanical so it really doesn't partially fail like that. I would expect LPFP or EPKM to be an all or nothing issue, not a low fuel flow issue.

Your octane is bad but that wont affect fuel quantity.

Yes, I agree with you but I have no idea where to start since it's my first time tuning the car. I'm already home, if you want to see how LTFT acts, I can take a little drive right now.

[ericlr1225]

Originally Posted by thejeremyman9

No ethanol? Your STFTs are quite positive, and LTFTs are not in the log, need those added.

https://www.bootmod3.net/log?id=636b...90c66aae957259

https://www.bootmod3.net/log?id=636b...0b439ed7c5f0d8

Just did one with LTFT on