idle edits

docs/Basic-Features/Idle Control/Closed-Loop_Idle_Control.md

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-# Closed loop idle control and how to set it up  
-
-Closed loop idle control uses a combination of closed loop timing adjustments and idle air control valve adjustments to achieve a stable idle. Achieving a stable idle can be difficult as it requires tuning two seperate controllers which operate in parallel to control the engine RPM. The best way to achieve a good idle is to use the closed loop idle timing for the larger and quicker corrections with the idle air controller acting to compensate for slower changes.
-
-Before tuning the closed loop idle, you need to have properly tuned the idle VE, idle ignition table and open loop idle control.

docs/Basic-Features/Idle Control/Idle-Tuning.md

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+# Idle Control and How to Set it  
+
+One of the most challenging aspects of achieving optimal engine performance is idle tuning. Unlike fueling, which can be quantified with instrumentation, idle tuning involves a range of options for achieving a specific RPM. However, the choices made in the process have a significant impact on the stability and robustness of the engine's idle.
+
+Idle can be compared to a see-saw with three main factors affecting it: fuel, ignition, and air. These elements determine the amount of torque produced by the engine, which in turn affects idle stability. To maintain a steady idle, the torque output must also remain relatively constant. Essentially, idle represents a state of balance, where the motor's load (caused by internal friction, accessories like the alternator, AC, torque converter/trans pump, or supercharger) is counterbalanced by the amount of torque generated by the engine. When load and torque are equal, there is no net acceleration, and the RPM remains constant. In essence, this is the overall concept to grasp.
+
+## Prerequisites to a Stable Idle
+
+The foundation for a stable idle is1 reliant on a motor that operates well. The quality of the fuel and ignition tuning around the idle region can significantly impact idle stability. It is crucial to tune the fueling in and around the idle region to maintain a consistent AFR, as any changes in AFR due to load or RPM can also affect the torque output.
+
+### Battery Voltage
+
+Battery voltage tends to be lowest at idle because the alternator is spinning at a slower speed. As a result, voltage can fluctuate frequently, especially when electrical loads such as blower motors and headlights are turned on or off. It is essential to fine-tune the battery and alternator control settings to prevent sudden AFR swings due to voltage changes. This can be challenging to tune, but intentionally creating electrical loads by turning on the headlights, AC or blower fans is a good way of changing the alternator load so it can be tuned to output a near constant voltage under all conditions.
+
+### Idle Air Control Valve Offsets
+
+Load can vary during idle and AC is the most significant factor that can significantly impact the engine load at idle. For engines equipped with an automatic transmission, the load in park/neutral is significantly different from that in drive. It is usually necessary to add IAC duty cycle/air to compensate for the torque required to spin the AC compressor. Again, it is crucial to ensure that AFRs don't swing excessively when moving between different idle operational areas. In the idle settings, start with about 10-15% for the *A/C adder (%)* parameter. As the AC increases the alternator load, the engine torque also needs to increase when the AC is enabled so it is recommended to do this by increasing the engine RPM by 100-200 with the *A/C target adder (RPM)*. The cooling fans also have associated adders (*Fan #x adder(%)*) although these don't usually need to be increased unless you notice a significant drop in RPM when the fans come on.
+
+
+## Open Loop Idle
+
+To determine the ideal idle RPM, you must consider various factors such as flywheel and rotating inertia, driven accessories via belt or gear, noise level, personal preference, among others. It may involve an iterative process of selecting a target RPM, attempting to achieve it, and revising expectations. Generally, higher RPM idling is more manageable because the engine produces more torque. 
+
+### Idle Airflow
+
+The first step of tuning the idle RPM is to set up the open loop idle airflow. Suppose you aim to set the engine to idle at 800 RPM (minimum), the airflow must be tuned to make the engine idle 50-150RPM higher than the 800 RPM target. This can be done by adjusting the *Open loop base position (%)* parameter, the idle adjustment screw, or the throttle end stop. It is recommended to tune these adjustments so the *Open loop base position (%)* parameter (which is the base duty cycle of the IACV) is at about 30% when the engine is 50-150RPM above target. This gives some room for the closed loop controller to adjust the duty cycle. It's essential to ensure that AFRs remain stable as you adjust the airflow. Before enabling idle control, a stable foundation is necessary. In this example, we will say that the engine idles at 950 RPM with 10 degrees of timing and 1.0 lambda.
+
+### Idle Ignition Table
+
+The idle ignition table acts much like the *open loop base position* in the regard that it is another open loop system contributing to the idle of the vehicle. Adjusting the engine ignition timing at idle changes the engine torque output where an increase in timing produces more torque and a reduction reduces the torque. This change in torque can be used to adjust the engine speed and achieve a stable idle by reducing the timing above the idle RPM target and increasing it below the target.
+
+To tune the ignition table, start by setting the maximum and minimum values about 500RPM above and below your target idle speed and interpolate the values between these. At your target idle speed in the table, put in your desired timing angle. 10 degrees is a good starting point but a higher timing angle such as 15 degrees will give the engine a bit more torque at idle which helps the engine to quickly rev up from idle. The idle timing angle will vary from engine to engine so it is always worth researching what others have used on your specific engine. 
+
+ The next step is to fill in the remaining cells of the idle timing table. At the minimum RPM, a value of 20 degrees is recommended as this is roughly where maximum brake torque (MBT) is. To fill in the gaps between the minimum and target RPM, use the interpolation button. For the maximum engine RPM value, a value in the range of 5-10 degrees less than the target is recommended (do not go below 0 degrees of timing). Once again, interpolate the values between the maximum RPM and target.
+  
+  Run the car with your values and see how well it maintains idle. Give it a few throttle blips to see how the idle settles. Start to adjust the timing values so that the timing pushes and pulls the engine RPM to the target and stabilizes within 50 RPM. You may need to change the shape of the curve so that only small timing adjustments are made near target and large corrections are made if the RPM significantly deviates. The trick is to essentially make a table of accurate guesses for what the timing will need to be in order to kick the engine RPM back to the target. The better your guesses are, the less work the closed loop timing controller will need to do when you implement it.
+
+# Closed Loop Idle  
+
+Closed loop idle control uses a combination of closed loop timing adjustments and idle air control valve adjustments to achieve a stable idle. Achieving a stable idle can be difficult as it requires tuning two seperate controllers which operate in parallel to control the engine RPM. The best way to achieve a good idle is to use the closed loop idle timing for the larger and quicker corrections with the idle air controller acting to compensate for slower changes.
+
+Before tuning the closed loop idle, you need to have properly tuned the idle VE, idle ignition table and open loop idle control.
+
+## Closed Loop Timing
+
+It is now time to turn on closed loop idle timing. It's important to note that closed loop idle should not make significant changes all the time for a stable idle. However, closed loop idle timing adjustment is crucial for long-term stability, and it's necessary to keep the engine idling when changes occur such as AC, headlights, fans, etc. Closed loop idle timing relies heavily on the proportional gain with little ot no derivative gain to act as a damper. A good place to start is with a proportional gain of 0.1 and a derivative gain of 0.05. To ensure the closed loop idle doesn't cause issues such as knocking, it's recommended to set boundaries on timing with an overall minimum and maximum. A good starting point is a -5 degree minimum and +5 degree maximum but these can be increased up to 10 degrees if you need more aggressive control.
+
+## Closed Loop Idle Air
+
+  Closed loop idle air control is a powerful tool, but one that requires extreme caution. Even small changes in airflow can have a significant impact, and the speed at which electronic throttle bodies or idle valves operate is much slower than spark control. To effectively use closed loop air control, a deadband must be established around the target to allow for minor corrections to work. If using Proportional adjustment, the gains should be kept low with a substantial deadband. Integral adjustment should dominate, again with a healthy deadband. Derivative adjustment is less important in this context. It's crucial to use closed loop air control carefully to avoid potential issues.

docs/Basic-Features/Idle Control/Open-Loop-Idle-Control.md

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-# Open Loop Idle Control and How to Set it  
-
-The open loop idle control is one of the first parameters to set when tuning the idle. It sets the base position of the idle air control valve (IACV) which the closed loop idle control leverages off to achieve finer idle control. The fundamental goal of tuning the open loop idle control is to set the base position such that the engine rests at the target idle RPM at the desired idle ignition timing angle.
-
-To tune the idle base position, enable the open loop idle and let the car warm up. Adjust the base position slider until the target RPM is close to desired. Take the car for a drive and re-adjust as necessary.