[rhenier99]

Hi guys, I was hoping someone could please have a look through these logs and see if something is off? I was driving slowly and the car wasn't warm yet when this drivetrain malfunction popped up.

I've been struggling with this error for a while now. I'm thinking it has something to do with the fuel supply but I'm not positive.

Please find codes and the log attached, the car is on a stock map in the attached log.

I also encountered the same error bm3 stage 1 91 octane map (surprise surprise). The malfunction occurred at the very end of the log, when the vehicle speed peaked and then dipped, here are the logs for that:

https://www.bootmod3.net/log?id=6507...0b430ffaa80c32

The car seems to be jerking and hesitating during WOT.

Thanks

[RoundEED]

Im ngl I can't tell too much from this but just from a first look standpoint, you have TONS of knocks in your logs which is most likely that issue. From experience I heard this is probably from octane or like something else, do you know what octane you are fueling with? Also was there any errors when you flashed the tune/did you follow everything exactly?

[rhenier99]

Originally Posted by RoundEED

Im ngl I can't tell too much from this but just from a first look standpoint, you have TONS of knocks in your logs which is most likely that issue. From experience I heard this is probably from octane or like something else, do you know what octane you are fueling with? Also was there any errors when you flashed the tune/did you follow everything exactly?

I always use 95 oct fuel (if it's really 95 is questionable though) but I've tried a few stations and it hasn't made a noticeable difference as far as I could see. Possible fuel tank contamination..? I took my car in to "specialists" so let's see what they come up with, I've replaced everything relating to the air fuel mixture more or less, all new plugs, coils and injectors. I also replaced the hpfp, I've tried cleaning the throttle body and intake valves (doubt it did much), I did all of this myself so hopefully I didn't screw it up but the car feels great in my opinion - the error seemingly comes out of nowhere. I did take it in to have the oil pump chain replaced, well actually I took it in for suspension and oil leak fixes, they found a piece of the timing chain guide in the oil sump so they put a new guide in and redid the oil pump chain. There was a vacuum leak that was fixed as well, I replaced the vanos solenoids, high grade oil change with engine flush, new oil and air filter, new mass airflow meter (using old one again as new one made no difference and old one is oem bosch). I also replaced the knock sensor itself (albeit I got one for a 320i) but alas that also made no difference (I've since put the old one back). I've been told the car's engine is healthy from a certified bmw master technician for what it's worth... so I'm really stumped as to what it could be.

[RoundEED]

Originally Posted by rhenier99

I always use 95 oct fuel (if it's really 95 is questionable though) but I've tried a few stations and it hasn't made a noticeable difference as far as I could see. Possible fuel tank contamination..? I took my car in to "specialists" so let's see what they come up with, I've replaced everything relating to the air fuel mixture more or less, all new plugs, coils and injectors. I also replaced the hpfp, I've tried cleaning the throttle body and intake valves (doubt it did much), I did all of this myself so hopefully I didn't screw it up but the car feels great in my opinion - the error seemingly comes out of nowhere. I did take it in to have the oil pump chain replaced, well actually I took it in for suspension and oil leak fixes, they found a piece of the timing chain guide in the oil sump so they put a new guide in and redid the oil pump chain. There was a vacuum leak that was fixed as well, I replaced the vanos solenoids, high grade oil change with engine flush, new oil and air filter, new mass airflow meter (using old one again as new one made no difference and old one is oem bosch). I also replaced the knock sensor itself (albeit I got one for a 320i) but alas that also made no difference (I've since put the old one back). I've been told the car's engine is healthy from a certified bmw master technician for what it's worth... so I'm really stumped as to what it could be.

Im not gonna lie after you did all this if its still knocking this much I have no clue what it could be, one thing i was thinking is maybe try going back to the stock tune driving a few days then logging and seeing if the knocks still occur but I don't really know. Maybe the tune is too aggressive?

[rhenier99]

Originally Posted by RoundEED

Im not gonna lie after you did all this if its still knocking this much I have no clue what it could be, one thing i was thinking is maybe try going back to the stock tune driving a few days then logging and seeing if the knocks still occur but I don't really know. Maybe the tune is too aggressive?

That's the thing, it's been on a stock tune for a few weeks, unfortunately this has been a problem pre tune as well (don't ask me why I did it then lol, not the sharpest tool in the shed I guess) I doubt it has anything to do with the tune, I don't realize a difference in when it pops up stock vs tuned, however obviously I'm sure it would knock more with a tune, but yeah again it's on a completely stock tune for a few weeks now. The weirdest part for me is that is says the noise is below limit value (or line interruption)... it might just maybe be a wiring issue.

[RoundEED]

Originally Posted by rhenier99

That's the thing, it's been on a stock tune for a few weeks, unfortunately this has been a problem pre tune as well (don't ask me why I did it then lol, not the sharpest tool in the shed I guess) I doubt it has anything to do with the tune, I don't realize a difference in when it pops up stock vs tuned, however obviously I'm sure it would knock more with a tune, but yeah again it's on a completely stock tune for a few weeks now. The weirdest part for me is that is says the noise is below limit value (or line interruption)... it might just maybe be a wiring issue.

Yeah im not gonna lie it could be something else i have no clue if you got everything else replaced it could be a faulty knock sensor
but anyways if i were you id try to get that fixed as knocks arent a MAJOR problem for a one time occurrence but if they happen consistently it could very badly damage your engine. aka no tune for now

[rhenier99]

Originally Posted by RoundEED

Yeah im not gonna lie it could be something else i have no clue if you got everything else replaced it could be a faulty knock sensor
but anyways if i were you id try to get that fixed as knocks arent a MAJOR problem for a one time occurrence but if they happen consistently it could very badly damage your engine. aka no tune for now

Thanks for the tips so far, I did replace the knock sensor, albeit with one from a 320i (still an n20 engine but obviously some differences) I wonder if a knock sensor from that would be different than a 328i... I know they're supposed to listen to a very specific frequency...