10-15-2021, 12:41 PM | #45 | |
Captain
175
Rep 643
Posts |
Quote:
OP, can you do a datalog of cruising at part throttle to see LTFT.
__________________
M235i rwd 6mt
|
|
Appreciate
0
|
10-15-2021, 12:52 PM | #46 | |
Major General
4364
Rep 7,606
Posts |
Quote:
That's why i am wondering if PTF can do a test by just disabling LTFTs entirely and see if the problem goes away. What i don't see in the log is target AFR, unless i am not recognizing it with BM3 labeling? |
|
Appreciate
0
|
10-15-2021, 05:18 PM | #47 |
Private First Class
28
Rep 125
Posts |
Further to this discussion about LTFT's, I observed the first screen shot during steady state driving on the freeway. About 1800-2000 RPM in top gear. With very light throttle I took the second screenshot. This is with the latest map from BM3. Clearly, the STFT's are fighting with the LTFT's.
With the stock tune the LTFT's are usually at 0 and never go beyond +/-3. Also, tested my fuel and it shows no more than 6% ethanol. I'm planning to put some logs up here later today or tomorrow and then I'm going to to load the BM3 Stage 2 ACN 91 map and see how the adaptions go with the MAF unplugged. |
Appreciate
0
|
10-15-2021, 05:25 PM | #48 | |
Major General
4364
Rep 7,606
Posts |
Quote:
The screenshot is consistent with your previous logs. LTFTs look normal until you go under load. It's strange because typically LTFTs don't change over such short timescales... |
|
Appreciate
0
|
10-15-2021, 05:28 PM | #49 |
Private First Class
28
Rep 125
Posts |
The LTFT's move around like the STFT"s are supposed to. Noticed that the first time I ran my gauge app. With the OEM tune the LTFT's behave normally.
|
Appreciate
0
|
10-15-2021, 05:35 PM | #50 |
Major General
4364
Rep 7,606
Posts |
Yeah strange... and the fact that the LTFTs behave normal on stock tune... could be software after all. If the MAF test doesn't work i would ask PTF if they can disable LTFTs entirely and test the OTS map with only that change.
|
Appreciate
0
|
10-16-2021, 09:27 PM | #51 |
Private First Class
28
Rep 125
Posts |
More logs.
This is the latest custom map from BM3 and I've been running it for about 400 miles, so it's adapted. Same story as before, FP crashes right after Lamba drops to the 11-10 range. I did notice that there are lean events in the 16-18 range prior to these crashes. I believe the system is reacting to those when the FP crashes. Loaded the Stage 2 ACN 91 map. I'm going to watch the LTFT's and confirm they swing wildly as before and then disconnect the MAF sensor and see if anything changes. After that, I'm loading the stock tune to confirm again nearly 0 LTFT"s. https://www.bootmod3.net/log?id=616b...729b18ec45e4d9 https://www.bootmod3.net/log?id=616b...729b197d4d5ba0 https://www.bootmod3.net/log?id=616b...90c66fb863c444 |
Appreciate
0
|
10-18-2021, 07:35 PM | #52 | |
Major General
4364
Rep 7,606
Posts |
Quote:
|
|
Appreciate
0
|
10-19-2021, 12:59 PM | #54 |
Major General
4364
Rep 7,606
Posts |
|
Appreciate
0
|
10-21-2021, 09:39 PM | #55 |
Private First Class
28
Rep 125
Posts |
After much work on the part of BM3 support, I finally have a map that maintains acceptable fuel pressure at WOT at all engine speeds and gears, and after adaptations.
While this is not a stage 2 tune, the progress is welcome and once BM3 has reviewed the logs stage 2 tunes with the same adjustments should be forthcoming. I just ran the logs and really haven't spent a lot of time analyzing them. https://www.bootmod3.net/log?id=6172...0b4322ec1a43e7 https://www.bootmod3.net/log?id=6172...0b4323724786f4 https://www.bootmod3.net/log?id=6172...729b197d4d7230 |
Appreciate
0
|
10-27-2021, 09:41 PM | #56 |
Private First Class
28
Rep 125
Posts |
Ran some new logs with the stage 2 OTS 91 ACN tune run with MAF unplugged.
https://www.bootmod3.net/log?id=6178...729b385163cab1 https://www.bootmod3.net/log?id=6178...90c6724ac74f1d https://www.bootmod3.net/log?id=6178...0b43484cd57fbc The previous logs show the throttle valve closing to limit fuel requirements during the conditions (RPM, throttle pos, boost, etc) which in previous logs the FP crashed. While this worked okay, the tune significantly limits power with boost capped around 14 psi. The stage 2 91 ACN tune with the MAF unplugged hits hard without FP issues after 25 miles of adaptations. Logs have about 50 miles. FP drops too much and there are timing corrections, but the dips into lean AFR's during full boost WOT don't seem as severe or as often as the logs with the MAF plugged in. Will put more time on this tune and post up more logs. |
Appreciate
0
|
10-28-2021, 05:50 PM | #57 | |
Major General
4364
Rep 7,606
Posts |
Quote:
Looked at the 2nd log a bit. I still see the same thing as before, where STFTs are fighting LTFTs and the AFR dips (rich) after the shifts, but HPFP isnt crashing, just small dips relative to target. Looks like throttle is also closing significantly on shift and boost target is pretty low which is lowering airflow. You also have a knock. |
|
Appreciate
0
|
10-28-2021, 05:56 PM | #58 | |
Major General
4364
Rep 7,606
Posts |
Quote:
The interesting thing on the fuel side is that, with the MAF unplugged, STFTs and LTFTs are reversed: LTFTs are slightly negative and STFTs are slightly positive. There are still a few small dips in HPFP pressure but it doesnt look like its for the same reason - no excessively rich AFRs and no high LTFTs driving the excess fuel. This is also a much higher boost level, and there arent really any throttle closures. Overall, the fuel trim and AFR behavior looks much more typical in the log with the MAF unplugged... |
|
Appreciate
0
|
10-28-2021, 08:09 PM | #59 |
Check out my Youtube @n55david!
1296
Rep 3,533
Posts
Drives: 2017 m240i, 2015 X3 x35i
Join Date: Aug 2018
Location: Michigan USA
|
my guy.. you have a mechanical problem with your fuel system. you need to get it fixed and stop having ptf try and bandaid your car.
__________________
2017 m240i xDrive 10.99@122.86mph bootmod3 stage 2+ ots
2015 335i xDrive 10.95@124.99mph w/bm3 - SOLD 2015 X3 x35i pwg 12.96 catless w/bm3 stage 2 93 ots IG: @n55david For pics and updates! Youtube: @ n55david For videos or Racing etc |
Appreciate
0
|
10-28-2021, 11:02 PM | #60 |
Private First Class
28
Rep 125
Posts |
I have tried 4 OTS maps, 3 custom BM3 Support maps and replaced a bunch of hardware and still this car won't run without issues on any of these tunes.
Without the MAF input does the computer run off speed- density maps with AFR feedback from the O2? What range does the MAF swing AFR's? I want to log the stock map and see what the LTFT and STFT's do with/without the MAF |
Appreciate
0
|
10-28-2021, 11:03 PM | #61 |
Private First Class
28
Rep 125
Posts |
|
Appreciate
0
|
10-29-2021, 12:23 AM | #62 | ||
Major General
4364
Rep 7,606
Posts |
Quote:
Quote:
But yeah testing stock map again to look at logs might be informative. |
||
Appreciate
1
n55david1295.50 |
10-29-2021, 06:49 AM | #63 |
Check out my Youtube @n55david!
1296
Rep 3,533
Posts
Drives: 2017 m240i, 2015 X3 x35i
Join Date: Aug 2018
Location: Michigan USA
|
100% guarantee you have a problem somewhere.
__________________
2017 m240i xDrive 10.99@122.86mph bootmod3 stage 2+ ots
2015 335i xDrive 10.95@124.99mph w/bm3 - SOLD 2015 X3 x35i pwg 12.96 catless w/bm3 stage 2 93 ots IG: @n55david For pics and updates! Youtube: @ n55david For videos or Racing etc |
Appreciate
0
|
10-29-2021, 11:59 AM | #64 |
Private First Class
28
Rep 125
Posts |
The easy answer is yes, there is a hardware problem with the car. However, there are zero issues with the stock tune or when I ran a JB4.
All the typical N55 problem areas have been addressed, coils, plugs, sensors, both fuel pumps, all 6 injectors, O2 sensor. The only failed component during the "shotgun" repairs was one FI slightly leaking. What could be failed/failing and not throw a code or be obvious? The Fuel Trims behave erratically with the PTF tunes and the adaptations seem to swing the AFR's and ultimately crash the fuel system after some miles. I've considered trying MHD, but BM3 was my preferred platform and clearly, these tunes should work fine for me like do for so many. |
Appreciate
0
|
10-29-2021, 12:44 PM | #65 | |
Major General
4364
Rep 7,606
Posts |
Quote:
|
|
Appreciate
0
|
10-29-2021, 12:59 PM | #66 | |
Private First Class
28
Rep 125
Posts |
Quote:
I have switched to another tune on the advice of support and will log that one with the MAF unplugged and we'll see if that makes a difference. I will post those logs as well. I'm looking again for leaks somewhere between the air cleaner and the turbo inlet, perhaps allowing unmetered air into the intake. Hard to believe that wouldn't be a full-time problem if it was happening but checking regardless. |
|
Appreciate
0
|
Post Reply |
Bookmarks |
Tags |
bootmod3, n55 fuel pressure crashing |
|
|