I would like to tune the idle of the car. The way the factory does it. I would like MS to catch the rpm before they fall below the desired idle target.
Here is the msq and a short datalog. I rev the engine to 3000rpm and lift the throttle. Idle target is 1000 rpm. But closed loop idle never catches the rpm falling down below the target.
Only when the engine bounce back from 800rpm to 1000 closed loop idle engages.
Any suggestion what idle parameters to check to engage closed loop before the revs fall below idle target? So the idle valves starts opening at maybe 1200rpm and slowly lands the engine revs
at desired idle target at 1000 rpm.
(I have a closed throttle idle (no idle control) at 900-950 rpm. Anything less and the engine stops when falling below 700 rpm when I release the throttle. )
Help with idle control needed
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Re: Help with idle control needed
It's trying, but not opening the valve enough. Try a higher sensitivity value or the initial duty table.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Re: Help with idle control needed
I noticed the CL Idle indicator in Tuner studio comes on only when rpms bounce back over 1000. CL idle does not engage when rpm are falling to catch the engine before is goes below 1000rpm, at least looking at Tunerstudio indicator.
Is there a parameter in the datalog that indicates when CL idle starts working ?
Is there a parameter in the datalog that indicates when CL idle starts working ?
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Re: Help with idle control needed
CL idle is not designed to catch the idle as it falls. That should be done by a combination of dashpot adder/initial value, ignition timing and fueling. By the time CL comes on, RPM should be stable and steady.
Megasquirt is not for use on pollution controlled vehicles. Any advice I give is for off road use only.
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Re: Help with idle control needed
Yep, welcome to the initial value table. It is recommended to use intake air temp on the y axis, because coolant temp is already factored into the x axis target rpm
Also if you are using a 2 wire pwm valve do you have a flyback diode fitted?
Also if you are using a 2 wire pwm valve do you have a flyback diode fitted?
RX7 Series 2 13B Turbo. Megasquirt 3 with 3X Expander and V3 CPU. Firmware 1.4.1
Knock module, twin EGT, real time clock, WBO2, full sequential fuel and spark
http://web.aanet.com.au/arran
Knock module, twin EGT, real time clock, WBO2, full sequential fuel and spark
http://web.aanet.com.au/arran
Re: Help with idle control needed
I do not have a flyback diode on the 2 wire pwm idle valve.
I found out that Status2 value 128 indicates when CL idle is active when looking at the datalog in log viever.
I will modify the IVT table to stabilize the idle when rpms are falling.
Maybe this information should be added the idle chapter in the MS manual, together with some advice on idle tuning with all this idle parameters.
Describing how to use Closed loop idle target RPM and Closed loop idle RPM error and Status 2 value 128 to , IVT table and how to use them to fine tune the idle.
Thank you for all the suggestions and advice.
I found out that Status2 value 128 indicates when CL idle is active when looking at the datalog in log viever.
I will modify the IVT table to stabilize the idle when rpms are falling.
Maybe this information should be added the idle chapter in the MS manual, together with some advice on idle tuning with all this idle parameters.
Describing how to use Closed loop idle target RPM and Closed loop idle RPM error and Status 2 value 128 to , IVT table and how to use them to fine tune the idle.
Thank you for all the suggestions and advice.