Idle drop and stall after change from open to closed loop idle
#23
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Thanks for sharing your inputs... Im at least getting my brain around the factors and variables. If I can summarize where I am at.
I have the stall show up in 3 areas:
1: at idle blipping throttle (1/30 times)
2: using power windows ( 80% of the time )
3: coaster to stop and depress clutch ( (1/30 )
The stall I am first trying to tune out is the one that happens every now and then stationary at idle when the throttle its blipped.
It will be fine 29/30 times then it will just fall straight to 500rpm,250rpm stall.
I have played with fuel cut, adder, pid, decel load etc and nothing changes the stall. It seems like it is happy then it just drops out.
When I look at the log the only factor that occurs prior to rpm drop (1/100 sec) is the duty cycle goes to zero.
Interestingly, also at idle I can stall the car using the power windows at the same time, I logged my battery volts during lights on and power windows and it looks to my untrained eye that it will stall if I demand any power which drops me below 12.8v, eg both power windows, even if my idle is 930rpm to start with.
I have played with settings to no reproduce-able improvement, anything look suspect? Yes I know I am pushing for a slapping for dumping too much info... and thank you. Happy to say that yesterday I changed from 425cc to 725cc injectors and it went perfectly today with just updating the ms3 settings for fuel load and dead time then retuning warm up enrichment and then the VE table with auto analyze... happy about that!
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I have the stall show up in 3 areas:
1: at idle blipping throttle (1/30 times)
2: using power windows ( 80% of the time )
3: coaster to stop and depress clutch ( (1/30 )
The stall I am first trying to tune out is the one that happens every now and then stationary at idle when the throttle its blipped.
It will be fine 29/30 times then it will just fall straight to 500rpm,250rpm stall.
I have played with fuel cut, adder, pid, decel load etc and nothing changes the stall. It seems like it is happy then it just drops out.
When I look at the log the only factor that occurs prior to rpm drop (1/100 sec) is the duty cycle goes to zero.
Interestingly, also at idle I can stall the car using the power windows at the same time, I logged my battery volts during lights on and power windows and it looks to my untrained eye that it will stall if I demand any power which drops me below 12.8v, eg both power windows, even if my idle is 930rpm to start with.
I have played with settings to no reproduce-able improvement, anything look suspect? Yes I know I am pushing for a slapping for dumping too much info... and thank you. Happy to say that yesterday I changed from 425cc to 725cc injectors and it went perfectly today with just updating the ms3 settings for fuel load and dead time then retuning warm up enrichment and then the VE table with auto analyze... happy about that!
![Name: Screenshot%207.png
Views: 1932
Size: 327.2 KB](https://www.miataturbo.net/attachments/megasquirt-18/184045d1501206632-idle-drop-stall-after-change-open-closed-loop-idle-screenshot%25207.png)
![Name: Screenshot%208.png
Views: 2002
Size: 284.4 KB](https://www.miataturbo.net/attachments/megasquirt-18/184046d1501206632-idle-drop-stall-after-change-open-closed-loop-idle-screenshot%25208.png)
![Name: Screenshot%209.png
Views: 1928
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#24
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Sorry for the slow update.
I have cracked and gone back to open loop idle. Perfect cold start, idle and never stalls...Ive spent the week fine tuning open loop settings and feel very satisfied.
Ill look back into closed loop later if I need to but for now the car feel like factory. Thanks for the inputs, it pointed me in the right direction.
I have cracked and gone back to open loop idle. Perfect cold start, idle and never stalls...Ive spent the week fine tuning open loop settings and feel very satisfied.
Ill look back into closed loop later if I need to but for now the car feel like factory. Thanks for the inputs, it pointed me in the right direction.
#25
Boost Czar
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thats just sad, and slightly pathetic.
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
#26
Retired Mech Design Engr
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thats just sad, and slightly pathetic.
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
#27
Elite Member
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thats just sad, and slightly pathetic.
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
Starting off by tuning open loop isn't a bad thing though. It stops you trying to use the PID routine to hide flaws in the basic tune.
#28
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
thats just sad, and slightly pathetic.
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
your PID values are still **** and you wonder why you're having issues with PID CL?
populate the initial values table with your open loop table, use initial value and not last known, put your TPS activation thresh back below 1% tps and actually plug in some good values in your CL settings...
When I tried to run of the initail values table the car wouldnt run, plus I had issues getting a good idle duty test as it would just stall at any values lower than 30. Ill get it running well on open and then go back to closed loop. I am working it backwards as I didnt do the original closed or open loop settings so thats why im missing the obvious perhaps.
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