So I'm reviewing a log and not sure what's happening. My throttle hung slightly open after a small acceleration. I blipped the throttle and it went back to normal idle voltage, but the car never saved itself. RPM's just kept falling. It shows the injection time picking up, but the AFR's are not matching that. I did notice it's highlighting the 'Fuel Cut' table until its under 500 RPM's, but not sure if that's related. Like if it's calculating the proper injection time, but not actually injecting anything? I'm guessing here.
Any pointers or tips would be helpful, because I'm not sure where to look right now.
Stalling on decel
Moderator: Matt
Stalling on decel
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- Nistune_2022-07-03_1910_43.csv
- (1.99 MiB) Downloaded 150 times
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- 7 3 22 - 6 21 22 with Up Min AAC.bin
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Re: Stalling on decel
This is an issue we see, where the airflow is still fairly high but the RPMs drop quickly
Since TP = K * MAF / RPM
As RPMs drop quick, the TP (yellow) increases, and so does the resulting injection time
So what is causing the airflow still to read (spinning turbo, lack of BOV venting airflow)? Once you resolve that, then the main goal is to drop the MAF voltage quicker, in line with RPM
Quick snaps of throttle and release may cause this. Limiting TPmax on the left most cells may assist a little (but may also affect acceleration)
Since TP = K * MAF / RPM
As RPMs drop quick, the TP (yellow) increases, and so does the resulting injection time
So what is causing the airflow still to read (spinning turbo, lack of BOV venting airflow)? Once you resolve that, then the main goal is to drop the MAF voltage quicker, in line with RPM
Quick snaps of throttle and release may cause this. Limiting TPmax on the left most cells may assist a little (but may also affect acceleration)
Re: Stalling on decel
If the mechanical fixes don't fix things, we have 11U0H available as a firmware update. However board needs remove and reflash using a base image progammer. In there are tables to limit TP when the throttle is released
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- 2022-07-05 16_21_46-Nistune [HCR32 SKYLINE (RB20DET) Feature Pack 1.0 (Version_ 4)].png
- (116.45 KiB) Downloaded 372 times
Re: Stalling on decel
Is that board reflash free?
Also do to packing constraints, the intake cannot be any different. So the injection time is too high essentially flooding the motor, making it impossible for it to recover itself?
Also do to packing constraints, the intake cannot be any different. So the injection time is too high essentially flooding the motor, making it impossible for it to recover itself?
Re: Stalling on decel
I don't provide any charge for the firmware files themselves (which are available for free in the ROM pack)
However, if the board/ECU is posted here then I charge for the time to download the original tune, remove and reflash the board and then import the tune and check the updates are all good, plus return postage
I do note your ECU was sent here for repair in Jan but we left the original tune and firmware 'as is' when it was received
However, if the board/ECU is posted here then I charge for the time to download the original tune, remove and reflash the board and then import the tune and check the updates are all good, plus return postage
I do note your ECU was sent here for repair in Jan but we left the original tune and firmware 'as is' when it was received