Haltech E6K - Manual (Page 89)

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Target Idle RPM
Target Idle RPM + Cold Idle-Up RPM
Target Idle RPM + Cold Idle-Up RPM + Start RPM
Engine Cold
Engine Warm
20sec 5-10 mins
RPM
Time
Number of Steps
This field controls the number of steps that the idle control will operate over. If you
have a stepper motor that uses say 150 steps, you can either elect to operate the stepper
motor over its entire range of steps by setting the value equal to the max number of
steps the motor will do which is 150 in this case, or you can restrict the number of
steps it can move through by making this field lower than 150. By restricting the
number of steps you can change the time response of the Idle Control but can also
affect the ability of the Idle Control to maintain control of the engine. This is because
in extreme circumstances the Idle Control may wish to move the stepper motor
through a large number of turns, but the Number of Steps on the stepper motor may
restrict the number of turns the motor can physically be permitted to move through,
thus reducing the Idle Control’s ability to control the engine as it desires.
It is best to start with a smaller value around 100 and increase it until the stepper motor
demonstrates that it is capable of bringing the engine to the target idle RPM. If the value is
too low, the stepper motor will not open enough to maintain a consistent idle, or if it is too
high, the stepper motor may actually miss pulses that are sent to it and therefore it will not
operate correctly.
Cold Temperature Limit
This is the temperature below which the engine is defined as being cold, and thus the
Cold Idle-Up and Cold Opening Steps would apply.
Cold Min Position
When the engine is cold, you can specify the minimum position the stepper motor will
return to. This is useful in some applications where valves besides the Idle Air Control
Motor can switch extra air flow into the engine that would otherwise confuse the Idle
Control into thinking the engine is behaving in a way which it is not. Start with a large
value around 80-90%% and reduce the value as you go. The idea is to move it down
until the engine is idling at such a point where it is close to the target rpm. The target
RPM is used to hold the idle once control of the engine has been established. Cold
Min Position is used to restrict the position of the controlling valve so when the Idle
Control wishes to regain control of the engine and bring it down to the target RPM it
actually will be able to. If the values you are using are around 80-90%, the Idle
Control will probably not be able to regain control of the engine and accurately bring
it down to the target idle RPM. This is why you must start with a large value for Cold
Min Position and reduce it until the engine is idling happily at the target RPM.