data log review

ajm55 · 10-18-2021, 09:13 AM

Here's a data log of a 3rd gear pull. This is a comp pack M5 with DPs and a mild tune. Anything untoward jump out of the attached log? I see that from about 6,700 rpm up, the AFRs on bank 2 lean out quite a bit more than on bank 1. Any idea as to the likely cause

https://datazap.me/u/ajm55/log-1634564072

M6Roar · 10-18-2021, 03:04 PM

mods? Just DP?

ajm55 · 10-18-2021, 09:26 PM

Just DPs and a tune that limits the torque below 5.000 rpm

M6Roar · 10-19-2021, 12:23 AM

I assume that you have boost leak. Wastegate is too high comparing to the boost car is making.

Unless you are at an elevation then that's normal.

ajm55 · 10-19-2021, 12:52 AM

Quote:

Originally Posted by M6Roar

I assume that you have boost leak. Wastegate is too high comparing to the boost car is making.

Unless you are at an elevation then that's normal.

Thanks for this. Yes, I am at 5,500 feet above sea level and assume therefore that the turbos will be working much harder to achieve target and will come up shy higher in the rev range

ajm55 · 10-20-2021, 01:59 PM

https://datazap.me/u/ajm55/log-1634755179

Here's another data log. Again, bank 1 and bank 2 AFRs are aligned until about 6,800 rpm when bank 2 AFRs lean out (well beyond target) and then timing on bank 2 goes into negative numbers.

Is anyone able to venture a guess or offer some advice as to what may be going on?

M6Roar · 10-21-2021, 12:38 AM

I would assume difference in turbo efficiency since you are 5,500 feet above sea level

by the time you reach 6,800 RPM the turbo got tired and cant keep up with the thin air so it would pump less air and DME will pull fuel and pull timing. Do a 3rd to 4th gear run and see if it levels back.

ajm55 · 10-21-2021, 04:27 AM

Quote:

Originally Posted by M6Roar

I would assume difference in turbo efficiency since you are 5,500 feet above sea level

by the time you reach 6,800 RPM the turbo got tired and cant keep up with the thin air so it would pump less air and DME will pull fuel and pull timing. Do a 3rd to 4th gear run and see if it levels back.

Thanks for the feedback. Don't think that's it though unless an issue with the bank 2 turbo has suddenly manifested. I have a gazillion logs - excuse the hyperbole - showing perfect alignment in the bank 1 and bank 2 AFRs right to the top. This issue has manifested in the last 10 days. Could a boost leak under pressure at the top of the rev range cause this? Alternatively a troublesome injector (although no codes are popping up)? I'll send the car in to the dealer next week and report back. This is well beyond my skill-set

M6Roar · 10-21-2021, 04:56 AM

what's your car mileage? usually boost leak will cause a rich AFR and not lean

M6Roar · 10-21-2021, 05:40 AM

can you log DME2?

ajm55 · 10-21-2021, 05:51 AM

Quote:

Originally Posted by M6Roar

can you log DME2?

Understood. Mileage is 70,000 kms. I'm using the MHD app to data log. Not sure about logging DME2 but will check this evening and revert, thanks

ajm55 · 10-21-2021, 10:53 PM

https://datazap.me/u/ajm55/log-1634834231

So I reloaded the stock tune to test and, as appears from the attached log, AFRs on both banks are aligned all the way to the top. You'll note that higher up in the rev range, the car makes similar boost on the stock file to what it makes on the tuned file (as it can't reach target boost on the tuned file because of the altitude).

I run about 10 - 15% eth and with this mix, on the tuned file my LTFTs gradually climb (on the plus side) over time. LTFTs get zero'd out whenever a different tune/file is loaded and I am wondering whether the LTFT reset when loading the stock file eliminated the issue of AFRs leaning out on bank 2. Next test will be to reload the BPM tune and see whether that eliminates the issue on that file too.

By the way, I am not able to log the DMEs with the MHD App

M6Roar · 10-22-2021, 04:17 AM

What makes me suspect that its a turbo efficiency or vacuum leak is that the wastegate is higher on bank 2 than bank 1, but it might be that the tune require some tweaking. (also increase the log sampling to log more accurately)

https://datazap.me/u/mohamed-albahi/...&data=1-4-8-18
https://www.bootmod3.net/log?id=60e9...729b2ee95dc961
https://www.bootmod3.net/log?id=5f3d...0b43133fd64a2d

It does reset adaptation when you reflash.

Did you speak to your tuner?

ajm55 · 10-22-2021, 11:23 AM

https://datazap.me/u/ajm55/22-oct-21...7100-2981-h-50

M6Roar, thanks for your input. This is not the most scintillating thread, I know.

Seems I jumped the gun. A quick pull (2nd gear) done on the stock file today produced the same issue so its definitely not tune related. Car's going to the dealer this coming week to check for vacuum leaks etc. I'll revert once I have feedback. BTW, how do I increase the log sampling? By running in 4th gear rather than 3rd?

M6Roar · 10-22-2021, 01:57 PM

Not sure but if you are using MHD its suppose to log more data than the current logs provided.

Thats your log rpm
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This is mine (logged by bm3)
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Yours are very far apart as there is alot goes on in the 300 to 600 rpm missing from each point.

ajm55 · 10-22-2021, 10:50 PM

Ok thanks. I’ll look into this

ajm55 · 10-23-2021, 08:15 AM

So to improve log sampling, I did a 4th gear run to 6,000 rpm and an uphill 3rd gear run to the top. Log sampling is still not as detailed as yours but nevertheless better than my previous logs.

The new logs cloud the issue even more (for me).

Here's the partial 4th gear log. You will see that even though I lifted the pedal just after 6,000 rpm (rather than allow the car to run to the top of the rev range), the issue still arose on bank 2 just before I came off the pedal

https://datazap.me/u/ajm55/23-oct-21...og=0&data=4-20

The next log is a 3rd gear run to the top (i.e. just over 7,100 rpm). Again, the issue arose on bank 2 just before I lifted off the pedal.

https://datazap.me/u/ajm55/23-oct-20...og=0&data=4-20

Not sure if these logs help or add to the confusion for you?

By the way, is this the tune on your car?

https://datazap.me/u/mohamed-albahi/...&data=1-4-8-18

I like it as it appears to limit the boost until you getting higher up in the rev range - something I was looking for, to make the car more drivable low down. If it is your vehicle, are you willing to share the details of your tuner?

M6Roar · 10-24-2021, 12:34 AM

I see that your AFR are within range at the moment for stock tune. usually tuners target 12.4 to 12.1 but on stock tune its higher. I still think your issue is thinner AIR and turbo efficiency. Look at your STFT% bank2 is adding more fuel. what fuel are you using? spraying straight water with a very small nozzle will help.

Yeah I added JB4 to compensate for few lost PSIs due to a larger cooler. Currently used as a boost control.

10-18-2021, 09:13 AM	#1
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	data log review Here's a data log of a 3rd gear pull. This is a comp pack M5 with DPs and a mild tune. Anything untoward jump out of the attached log? I see that from about 6,700 rpm up, the AFRs on bank 2 lean out quite a bit more than on bank 1. Any idea as to the likely cause https://datazap.me/u/ajm55/log-1634564072
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10-18-2021, 03:04 PM	#2
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	mods? Just DP?
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10-18-2021, 09:26 PM	#3
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	Just DPs and a tune that limits the torque below 5.000 rpm
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10-19-2021, 12:23 AM	#4
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	I assume that you have boost leak. Wastegate is too high comparing to the boost car is making. Unless you are at an elevation then that's normal. Last edited by M6Roar; 10-19-2021 at 12:47 AM..
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10-20-2021, 01:59 PM	#6
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	https://datazap.me/u/ajm55/log-1634755179 Here's another data log. Again, bank 1 and bank 2 AFRs are aligned until about 6,800 rpm when bank 2 AFRs lean out (well beyond target) and then timing on bank 2 goes into negative numbers. Is anyone able to venture a guess or offer some advice as to what may be going on?
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10-21-2021, 12:38 AM	#7
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	I would assume difference in turbo efficiency since you are 5,500 feet above sea level by the time you reach 6,800 RPM the turbo got tired and cant keep up with the thin air so it would pump less air and DME will pull fuel and pull timing. Do a 3rd to 4th gear run and see if it levels back.
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10-21-2021, 04:56 AM	#9
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	what's your car mileage? usually boost leak will cause a rich AFR and not lean
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10-21-2021, 05:40 AM	#10
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	can you log DME2?
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10-21-2021, 10:53 PM	#12
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	https://datazap.me/u/ajm55/log-1634834231 So I reloaded the stock tune to test and, as appears from the attached log, AFRs on both banks are aligned all the way to the top. You'll note that higher up in the rev range, the car makes similar boost on the stock file to what it makes on the tuned file (as it can't reach target boost on the tuned file because of the altitude). I run about 10 - 15% eth and with this mix, on the tuned file my LTFTs gradually climb (on the plus side) over time. LTFTs get zero'd out whenever a different tune/file is loaded and I am wondering whether the LTFT reset when loading the stock file eliminated the issue of AFRs leaning out on bank 2. Next test will be to reload the BPM tune and see whether that eliminates the issue on that file too. By the way, I am not able to log the DMEs with the MHD App Last edited by ajm55; 10-22-2021 at 01:30 AM.. Reason: adding further info
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10-22-2021, 04:17 AM	#13
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	What makes me suspect that its a turbo efficiency or vacuum leak is that the wastegate is higher on bank 2 than bank 1, but it might be that the tune require some tweaking. (also increase the log sampling to log more accurately) https://datazap.me/u/mohamed-albahi/...&data=1-4-8-18 https://www.bootmod3.net/log?id=60e9...729b2ee95dc961 https://www.bootmod3.net/log?id=5f3d...0b43133fd64a2d It does reset adaptation when you reflash. Did you speak to your tuner?
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10-22-2021, 11:23 AM	#14
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	https://datazap.me/u/ajm55/22-oct-21...7100-2981-h-50 M6Roar, thanks for your input. This is not the most scintillating thread, I know. Seems I jumped the gun. A quick pull (2nd gear) done on the stock file today produced the same issue so its definitely not tune related. Car's going to the dealer this coming week to check for vacuum leaks etc. I'll revert once I have feedback. BTW, how do I increase the log sampling? By running in 4th gear rather than 3rd?
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10-22-2021, 01:57 PM	#15
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	Not sure but if you are using MHD its suppose to log more data than the current logs provided. Thats your log rpm This is mine (logged by bm3) Yours are very far apart as there is alot goes on in the 300 to 600 rpm missing from each point.
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10-22-2021, 10:50 PM	#16
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	Ok thanks. I’ll look into this
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10-23-2021, 08:15 AM	#17
ajm55 Private First Class 52 Rep 175 Posts Drives: f10 m5 Join Date: Dec 2019 Location: south africa iTrader: (0)	So to improve log sampling, I did a 4th gear run to 6,000 rpm and an uphill 3rd gear run to the top. Log sampling is still not as detailed as yours but nevertheless better than my previous logs. The new logs cloud the issue even more (for me). Here's the partial 4th gear log. You will see that even though I lifted the pedal just after 6,000 rpm (rather than allow the car to run to the top of the rev range), the issue still arose on bank 2 just before I came off the pedal https://datazap.me/u/ajm55/23-oct-21...og=0&data=4-20 The next log is a 3rd gear run to the top (i.e. just over 7,100 rpm). Again, the issue arose on bank 2 just before I lifted off the pedal. https://datazap.me/u/ajm55/23-oct-20...og=0&data=4-20 Not sure if these logs help or add to the confusion for you? By the way, is this the tune on your car? https://datazap.me/u/mohamed-albahi/...&data=1-4-8-18 I like it as it appears to limit the boost until you getting higher up in the rev range - something I was looking for, to make the car more drivable low down. If it is your vehicle, are you willing to share the details of your tuner? Last edited by ajm55; 10-23-2021 at 08:32 AM.. Reason: adding content
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10-24-2021, 12:34 AM	#18
M6Roar Second Lieutenant 86 Rep 242 Posts Drives: '14 M6GC Join Date: Apr 2018 Location: Bahrain iTrader: (0)	I see that your AFR are within range at the moment for stock tune. usually tuners target 12.4 to 12.1 but on stock tune its higher. I still think your issue is thinner AIR and turbo efficiency. Look at your STFT% bank2 is adding more fuel. what fuel are you using? spraying straight water with a very small nozzle will help. Yeah I added JB4 to compensate for few lost PSIs due to a larger cooler. Currently used as a boost control. Last edited by M6Roar; 10-24-2021 at 12:39 AM..
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