[IMS-340C]

True mate I always try to avoid full throttle low RPM high gear situation.

I already de-tuned the OEM MPPSK tune from 500nm@4800 RPM down to 450nm@4800 RPM and to 372nm (340 HP)@6500 RPM (Attached).

Guys anybody know what's the most common cause of Boost Actual exceeding Boost Target ?

https://datazap.me/u/ims/ims-mppsk-4...=0&data=4-6-16

Originally Posted by XutvJet

This is the very situation I'm talking about regarding LSPI. High load, low rpm.

Definitely swap the stock DP back in and see if it remedies the issue. Your tune may be too aggressive for the climate, altitude, and octane you're running. Dial it back and stop going full throttle from 2500rpms in the taller gears. Downshift if you need the passing power.

[CoolATIGuy]

What did you end up figuring out here?

[BoostleakTV]

Originally Posted by IMS-340C

True mate I always try to avoid full throttle low RPM high gear situation.

I already de-tuned the OEM MPPSK tune from 500nm@4800 RPM down to 450nm@4800 RPM and to 372nm (340 HP)@6500 RPM (Attached).

Guys anybody know what's the most common cause of Boost Actual exceeding Boost Target ?

https://datazap.me/u/ims/ims-mppsk-4...=0&data=4-6-16

Slight overboost after gear change is completely normal. It’s inherent to the turbo system design.

[abbike18]

Originally Posted by IMS-340C

True mate I always try to avoid full throttle low RPM high gear situation.

I already de-tuned the OEM MPPSK tune from 500nm@4800 RPM down to 450nm@4800 RPM and to 372nm (340 HP)@6500 RPM (Attached).

Guys anybody know what's the most common cause of Boost Actual exceeding Boost Target ?

https://datazap.me/u/ims/ims-mppsk-4...=0&data=4-6-16

Log compressor base kw and after PID - you likely need to adjust your compressor map down to request less power from the turbine (and keep the WG more open)

[Reu]

I'm having the same issue in my N20 328i when i give it WOT. I've been data logging for the past 2 months going back and forth with BM3 trying out different maps but we cannot find the reason why the car is knocking randomly. The thing is that sometimes the car does not knock at all and no ignition timing corrections and then all of a sudden the car starts knocking and pulling timing again.

My car is full bolt ons. I have changed the plugs(gaped to 0.022), coils and even the knock sensors. Checked the whole ignition harness and it looks in good condition. I even give it good premium quality fuel and even octane boosters but the car still keeps on knocking. Sometimes it gets so bad that it cuts ignition due to super knocks.

The strange thing is that when reverting back to the stock tune the car works perfectly fine with no knocks at all. This is a brand new engine from BMW with now 5000km. Also with the engine i bought brand new injectors(before buying i confirmed that they are the correct ones).

Recently BM3 made me a tune that is made for the mods i have and the car was finally working great but again it started to knock and pulling timing for no reason. I honestly have no clue what to do from here.

Did somebody ever encounter this problem ? Thanks

[enemigo13]

it is easy to test. Add 15-20litres of E85 to the full tank and check if knocking goes away. If it does - then you need better octane than you're currently running or more conservative timing. If it doesn't - it means you're getting false knock. False knock is eliminated through lowering knock sensitivity.

Originally Posted by Reu

I'm having the same issue in my N20 328i when i give it WOT. I've been data logging for the past 2 months going back and forth with BM3 trying out different maps but we cannot find the reason why the car is knocking randomly. The thing is that sometimes the car does not knock at all and no ignition timing corrections and then all of a sudden the car starts knocking and pulling timing again.

My car is full bolt ons. I have changed the plugs(gaped to 0.022), coils and even the knock sensors. Checked the whole ignition harness and it looks in good condition. I even give it good premium quality fuel and even octane boosters but the car still keeps on knocking. Sometimes it gets so bad that it cuts ignition due to super knocks.

The strange thing is that when reverting back to the stock tune the car works perfectly fine with no knocks at all. This is a brand new engine from BMW with now 5000km. Also with the engine i bought brand new injectors(before buying i confirmed that they are the correct ones).

Recently BM3 made me a tune that is made for the mods i have and the car was finally working great but again it started to knock and pulling timing for no reason. I honestly have no clue what to do from here.

Did somebody ever encounter this problem ? Thanks

[Reu]

enemigo13

I don't believe it is false knock as i do physically hear it especially but only when there are super knocks(sounds like hissing mixed with switching on a switch if that helps to explain the sound ). I also removed the plugs sometimes right after a run where it knocks and i can clearly see like white marks. At first i thought i was leaning out but in the logs AFR and fuel pressure are always hitting their target. I got some opinions that said that the white marks represent pre-ignition and overheating the plugs(I have the NGK 97506).

Regarding fuel we already confirmed that its not related as i tested out bad 93 and good 93 and with good 93 the car changed completely with better ignition timing but still i was getting knocks. I have an M4 and i give it the same fuel and I've been with stage 1 93oct for 2yrs and a half straight and i never get knocks. Unfortunately to get hands on E85 in my country is quite expensive since it is not served in petrol stations and only one guy imports it.

[enemigo13]

if you feel difference between "good" and "bad" 93 then issue is fuel related. you should run less aggressive tune or run with stock software as N20 is not so forgiving like S55 or B58.

Originally Posted by Reu

enemigo13

I don't believe it is false knock as i do physically hear it especially but only when there are super knocks(sounds like hissing mixed with switching on a switch if that helps to explain the sound ). I also removed the plugs sometimes right after a run where it knocks and i can clearly see like white marks. At first i thought i was leaning out but in the logs AFR and fuel pressure are always hitting their target. I got some opinions that said that the white marks represent pre-ignition and overheating the plugs(I have the NGK 97506).

Regarding fuel we already confirmed that its not related as i tested out bad 93 and good 93 and with good 93 the car changed completely with better ignition timing but still i was getting knocks. I have an M4 and i give it the same fuel and I've been with stage 1 93oct for 2yrs and a half straight and i never get knocks. Unfortunately to get hands on E85 in my country is quite expensive since it is not served in petrol stations and only one guy imports it.

[Reu]

Originally Posted by enemigo13

if you feel difference between "good" and "bad" 93 then issue is fuel related. you should run less aggressive tune or run with stock software as N20 is not so forgiving like S55 or B58.

I tried ACN tunes and also 91oct tunes and i still was getting knocks. I only am on stage 1 but the most consistent tune that the car performed amazingly was in Stage 2 93oct and i rarely rarely got knocks and ignition timing was always on point. I confirmed that the 93oct from Enemed(the only reputable fuel that we have in my country) is good quality. I have many runs where timing is bang on perfect throughout the whole rev range and BM3 confirmed that the car is performing great. The strange thing is that then lets say the next day the car starts knocking or cutting ignition. I reflash a tune, all is good after 8 runs but then the car starts knocking again.

Could this be ECU related ? i had a 20i before but when i bought the new engine i got the 28i version directly from BMW. Of course the the ECU was reprogrammed to a 28i since they are the same.

[weehe126]

Those plugs look horrible. Are you using octane booster every fill up? If you aren't then you have a serious issue.

[enemigo13]

drive with stock tune until you'll find issue

Originally Posted by Reu

I tried ACN tunes and also 91oct tunes and i still was getting knocks. I only am on stage 1 but the most consistent tune that the car performed amazingly was in Stage 2 93oct and i rarely rarely got knocks and ignition timing was always on point. I confirmed that the 93oct from Enemed(the only reputable fuel that we have in my country) is good quality. I have many runs where timing is bang on perfect throughout the whole rev range and BM3 confirmed that the car is performing great. The strange thing is that then lets say the next day the car starts knocking or cutting ignition. I reflash a tune, all is good after 8 runs but then the car starts knocking again.

Could this be ECU related ? i had a 20i before but when i bought the new engine i got the 28i version directly from BMW. Of course the the ECU was reprogrammed to a 28i since they are the same.

[Reu]

Originally Posted by weehe126

Those plugs look horrible. Are you using octane booster every fill up? If you aren't then you have a serious issue.

Yes every fill up i give it octane booster.

[Reu]

Originally Posted by enemigo13

drive with stock tune until you'll find issue

Yepp currently its in stock form.

I bought fresh plugs as I got some opinions that the plugs got so overheated due to pre-ignition that they may have just stopped working properly. I'll update this thread after I install them.

[Reu]

So last weekend i changed the plugs to a brand new set and after some runs i couldn't see any knock being detected finally. Wanted to do some more tests the next day to confirm if the knocks really went away for good but unfortunately whilst getting out of my garage the turbo started sounding like an ambulance siren and i immediately new that the turbo was blown. Quite pissed as it is freshly rebuilt.

When i get the turbo fixed i will re test again and update this thread.

[Ak1221]

Originally Posted by Reu

So last weekend i changed the plugs to a brand new set and after some runs i couldn't see any knock being detected finally. Wanted to do some more tests the next day to confirm if the knocks really went away for good but unfortunately whilst getting out of my garage the turbo started sounding like an ambulance siren and i immediately new that the turbo was blown. Quite pissed as it is freshly rebuilt.

When i get the turbo fixed i will re test again and update this thread.

Any updates on the progress