[Quick335XI]

We've been trying to tune my car for months now; the latest is, the trim values look decent now, but for some reason on cylinder #4 it consistently is pulling alot of timing. Sometimes, around 5500rpm, I'll hear a "fluttering" or grinding noise, then I'll get a superknocking code - but what's very weird is, code says superknocking on cylinder SIX. smh

I had my plugs pulled not long ago and they looked absolutely pristine, no signs of any knocking, rich, lean, nothing. Does anyone know what this sound is? I've never had a car superknock before so I'm not sure if that's actually what it is, or that's the sound of the computer retarding the timing.

With other tunes we tried, other cylinders were pulling timing and #4 was ok. Very weird, and very frustrating. Also, i had index 12 injectors put in about a year ago.

https://datazap.me/u/terryeaton/log-...og=0&data=3-21

ANy ideas what is going on here??!? The motor has about 15k on it, and it has JE forged pistons, steel rods the whole 9 yards, it should be able to take 35psi for sure.

[Saif2018]

Originally Posted by tej98

Thanks! Yeah, I reset adaptations and ensured that all the injector flow rates are coded properly (I used INPA). It was my understanding that official guidance from BMW was to keep each bank either on all index 11/12, or they could mix indexes as long as they were below 11.

I currently have bank one with all index 12s and bank two with two index 5s and one index 6.

I pulled another log after resetting lambda adaptations and have the exact same results. The maximum difference in STFTs between banks is ~13%, with bank one at 18% and bank 2 at 5%. AFRs are still steady at ~12 for both banks.

Do the trims max out at 34%? If so, I'd think there should be plenty of headroom for fluctuation by the DME if needed. Or is that generally not enough?

Thanks!

Yes they max out +/- 34% of I recall correctly.

Have you swapped the injectors round to see if STFT follow?

[Sgop335]

Originally Posted by Quick335XI

We've been trying to tune my car for months now; the latest is, the trim values look decent now, but for some reason on cylinder #4 it consistently is pulling alot of timing. Sometimes, around 5500rpm, I'll hear a "fluttering" or grinding noise, then I'll get a superknocking code - but what's very weird is, code says superknocking on cylinder SIX. smh

I had my plugs pulled not long ago and they looked absolutely pristine, no signs of any knocking, rich, lean, nothing. Does anyone know what this sound is? I've never had a car superknock before so I'm not sure if that's actually what it is, or that's the sound of the computer retarding the timing.

With other tunes we tried, other cylinders were pulling timing and #4 was ok. Very weird, and very frustrating. Also, i had index 12 injectors put in about a year ago.

https://datazap.me/u/terryeaton/log-...og=0&data=3-21

ANy ideas what is going on here??!? The motor has about 15k on it, and it has JE forged pistons, steel rods the whole 9 yards, it should be able to take 35psi for sure.

What plugs, gap and coils?
The obvious check is w lower timing and or boost to see if this changes. The noise could be detonation but why cyl 6 is not correcting?

[Quick335XI]

Originally Posted by Sgop335

What plugs, gap and coils?
The obvious check is w lower timing and or boost to see if this changes. The noise could be detonation but why cyl 6 is not correcting?

Hi,

Plus are NGK 97506 gapped to .018, changed a couple months ago. The old ones were pristine, barely any sign of use and had been in the car for almost a year.

As for changing the timing and such, what's weird is, I did four pulls yesterday; they all had very little timing pulls except one, and I don't even think that's the one I got the superknocking code on. Trims look good now, etc And again it said superknocking on #6 when #6 has 0 timing pull. So frustrating! Here's ac ouple more logs from yesterday:

https://datazap.me/u/terryeaton/log-...og=0&data=3-21

https://datazap.me/u/terryeaton/log-...og=0&data=3-21

I'm not sure if that fluttering sound is "actual" knock, or the computer/car retarding the timing. If it's not real knock, maybe I should dsensitize the knock tables or something? Not sure

[tej98]

Originally Posted by Saif2018

Yes they max out +/- 34% of I recall correctly.

Have you swapped the injectors round to see if STFT follow?

I haven't swapped the injectors around yet. Am I correct in thinking that if the trims are not maxed out in either direction they should be fine? In my specific case it seems even with bank 1 around 20% that should leave enough headroom for adjustments?

Thanks!

[Saif2018]

Originally Posted by tej98

I haven't swapped the injectors around yet. Am I correct in thinking that if the trims are not maxed out in either direction they should be fine? In my specific case it seems even with bank 1 around 20% that should leave enough headroom for adjustments?

Thanks!

Yes but not ideal.

Tuning adjustments should help.

[Sgop335]

Originally Posted by Quick335XI

Hi,

Plus are NGK 97506 gapped to .018, changed a couple months ago. The old ones were pristine, barely any sign of use and had been in the car for almost a year.

As for changing the timing and such, what's weird is, I did four pulls yesterday; they all had very little timing pulls except one, and I don't even think that's the one I got the superknocking code on. Trims look good now, etc And again it said superknocking on #6 when #6 has 0 timing pull. So frustrating! Here's ac ouple more logs from yesterday:

https://datazap.me/u/terryeaton/log-...og=0&data=3-21

https://datazap.me/u/terryeaton/log-...og=0&data=3-21

I'm not sure if that fluttering sound is "actual" knock, or the computer/car retarding the timing. If it's not real knock, maybe I should dsensitize the knock tables or something? Not sure

2/3 logs I think are showing large timing corrections on cyl 4. Must be a reason for that. Either the fuel is not good enough or the timing/boost is too high for the fuel. I would not desentize knock tables.
Cyl 4 is showing such high corrections it is basically firing after TDC. Why superknock on cyl 6 is not clear to me but I can at least see that cyl 4 is not doing well.

[Quick335XI]

Originally Posted by Sgop335

2/3 logs I think are showing large timing corrections on cyl 4. Must be a reason for that. Either the fuel is not good enough or the timing/boost is too high for the fuel. I would not desentize knock tables.
Cyl 4 is showing such high corrections it is basically firing after TDC. Why superknock on cyl 6 is not clear to me but I can at least see that cyl 4 is not doing well.

Thanks, any suggestions on figuring out why it’s doing that ?

[Quick335XI]

Originally Posted by Sgop335

2/3 logs I think are showing large timing corrections on cyl 4. Must be a reason for that. Either the fuel is not good enough or the timing/boost is too high for the fuel. I would not desentize knock tables.
Cyl 4 is showing such high corrections it is basically firing after TDC. Why superknock on cyl 6 is not clear to me but I can at least see that cyl 4 is not doing well.

Btw, there are Elder coils about a year old

[Sgop335]

Originally Posted by Quick335XI

Thanks, any suggestions on figuring out why it’s doing that ?

Suggestions,
Are you sure car is also not misfiring ? It’s difficult to pick up spark blowout or misfire in logs. But it can be felt by driver. The rpms are also typically choppy in logs.
Once i also resetted knock adaptations.
I prefer eldor coils too but they need to be tight w the spark plug, dielectric grease helped for me to insulate gaps.
I like to have lower timing at 4k to 4.5k then ramp up as rpm increases..

[ddakarr]

Would someone mind taking a look at this? Recently did catless DP with MHD stage 2 tune on 91oct (all we have in AZ). Blew factory charge pipe and car is now feeling kind of sluggish when doing pulls.
Car is n55 135i
Timing corrections seem high to me
boost drops off from target as RPMs rise
STFTs seem very low
WGDC seems very high

Could be a boost leak? Or maybe the tune is too much for 91oct?

Thanks in advance.

https://datazap.me/u/whtkrkid/log-16...-38&zoom=15-70

[Quick335XI]

Originally Posted by Sgop335

Suggestions,
Are you sure car is also not misfiring ? It’s difficult to pick up spark blowout or misfire in logs. But it can be felt by driver. The rpms are also typically choppy in logs.
Once i also resetted knock adaptations.
I prefer eldor coils too but they need to be tight w the spark plug, dielectric grease helped for me to insulate gaps.
I like to have lower timing at 4k to 4.5k then ramp up as rpm increases..

I don’t believe it’s misfiring, not that I can tell… my PI is over 3 years old, so the injectors ever need cleaning? Thst was one thought I had, maybe one of the PI injectors on cylinder 4 is not flowing that great.

[KrazyKiwi]

Hi Everyone,

Just did a log after flashing Stage 2+ on my FBO car. Could someone please provide some feedback.

https://datazap.me/u/krazykiwi/mhd-v9-stage2-run1?log=0&data=3-4-20

Cheers!

[Saif2018]

Originally Posted by KrazyKiwi

Hi Everyone,

Just did a log after flashing Stage 2+ on my FBO car. Could someone please provide some feedback.

https://datazap.me/u/krazykiwi/mhd-v9-stage2-run1?log=0&data=3-4-20

Cheers!

Looks fine mate,

[Quick335XI]

Since we can't figure out these big timing pulls on cylinder 4 at this time, the tuner de-tuned the car a bit... it's a little frustrating because this is a closed deck block with steel rods and forged pistons and all I'm able to run without big timing pulls is like 26psi I guess for now I'll just leave it like this and when I get the funds, look at getting the Reflex setup. maybe one of my PI injectors isn't flowing well(?). I was really hoping to be able to dial it in and get it on the dyno soon

AnywaY here are the three logs I just did with a bit of de-tuning:

Run #1: https://datazap.me/u/terryeaton/log-...og=0&data=3-21
Run #2: https://datazap.me/u/terryeaton/log-...og=0&data=3-21
Run #3: https://datazap.me/u/terryeaton/log-...og=0&data=3-21

Any thoughts welcome, thanks

[EvanS]

I've linked to two logs for back-to-back 3rd gear pulls. First pull felt good. Second pull threw 29DC code, but looking at the logs I think it might be a LPFP issue. LPFP swings wildly up and down, drops below 40psi, HPFP drops out to below 500psi, STFT maxes, and engine throws code/enters limp mode.

This seems to be happening more recently, preceded by what seem like excessive swings in LPFP and misfires.

I could use some help from more experienced folks to help troubleshoot the issue.

Thanks!
https://datazap.me/u/evans/december-...og=0&data=3-22

https://datazap.me/u/evans/december-...-12-22&hg=3-12

[strmix]

Originally Posted by EvanS

I've linked to two logs for back-to-back 3rd gear pulls. First pull felt good. Second pull threw 29DC code, but looking at the logs I think it might be a LPFP issue. LPFP swings wildly up and down, drops below 40psi, HPFP drops out to below 500psi, STFT maxes, and engine throws code/enters limp mode.

This seems to be happening more recently, preceded by what seem like excessive swings in LPFP and misfires.

I could use some help from more experienced folks to help troubleshoot the issue.

Thanks!
https://datazap.me/u/evans/december-...og=0&data=3-22

https://datazap.me/u/evans/december-...-12-22&hg=3-12

I would say its your hpfp failing, because you still have good low pressures.

[F13.KENN]

https://datazap.me/u/schwarze92/mhd-...&data=3-20

Anything look off on here? 60 rolled my friends 370z today and surprised he wasnt that much slower than me. What looks weird to me is that my car doesnt seem to make boost till 5k rpms. Its been 80k miles since boost solenoids were changed. Currently at 216k miles

His 370 is fbo & tuned

Edit: noticed i was reading RPM wrong

[eastsidaz]

Originally Posted by SCHWARZ_E92

https://datazap.me/u/schwarze92/mhd-...og=0&data=3-20

Anything look off on here? 60 rolled my friends 370z today and surprised he wasnt that much slower than me. What looks weird to me is that my car doesnt seem to make boost till 5k rpms. Its been 80k miles since boost solenoids were changed. Currently at 216k miles

His 370 is fbo & tuned

Yeah certainly seems quite unresponsive and very slow to build boost. WGDC is quite high in 70+ in the higher rpm's. Most in this area would be in the 50's. Possibly solenoids or maybe worn turbos

Also noticed Fuel trims are quite high aswell. Not sure why its happening have your tried to reset adaptions?

[Tkent818]

https://datazap.me/u/tkent818/log-16...&data=3-21

Just wondering what you guys think, mods are in my sig and this is a baseline map. Waiting on a revision from Ken

[Saif2018]

Originally Posted by Tkent818

https://datazap.me/u/tkent818/log-16...og=0&data=3-21

Just wondering what you guys think, mods are in my sig and this is a baseline map. Waiting on a revision from Ken

HPFP (rail pressure) taking a nosedive after 6k rpm, that's not good.

Turbos seem pretty laggy, taking almost 1000rpm to reach boost target.

[Tkent818]

Originally Posted by Saif2018

HPFP (rail pressure) taking a nosedive after 6k rpm, that's not good.

Turbos seem pretty laggy, taking almost 1000rpm to reach boost target.

O ya I just saw that rail pressure thing right now, maybe back the E off a little bit? At least until I can get a new pump and/or PI? I addressed the lagging thing with Ken in the email, it feels like it takes a long to get to red line. What can I do for that?