Haltech E6K - Manual (Page 60)

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CHAPTER 7 COLD STARTING AND RUNNING
The Haltech E6K has four features to modify fuel delivery and ignition timing to aid in
starting and running a cold engine. The Cold Start Prime map gives a cold engine an initial
burst of fuel just as the engine begins cranking. The Coolant Correction Map modifies the
normal fuel injection until the engine reaches normal operating temperatures. The Ignition
Cranking Map set the crank advance for different coolant temperatures. And finally, the
Ignition Coolant Map modifies the ignition advance from the Ignition Map for different
coolant temperatures.
7.1 Cold Cranking
At cold crank the air speed at the inlet manifold is very low. As a result a lot of fuel that
would normally travel in the air, sticks to the manifold walls and doesn't enter the engine. The
cylinder chamber temperatures are also low which leads to poor combustion. To overcome
these inefficiencies, it is necessary to prime the engine with a long pulse of the injectors at the
start of cranking to ensure that the engine has enough fuel in the cylinder to fire.
The E6K provides a cold start fuel prime that is adjustable at all engine temperatures. This
allows the duration of the prime pulse to be optimised for cold cranking under a wide variety
of conditions. Access the Cold Start Prime function from the Fuel Maps and Set-up Menu.
The cold prime map specifies an injection time based on engine coolant temperature. The
height of the bars define the actual duration that the injectors are open. A typical map is
already loaded into your E6K and this should not need to be modified unless you are having
trouble cold starting the engine. Any changes like this should be done ONLINE, so the
change can be reversed if the engine becomes harder to start.
Over priming the engine will cause it to flood and not start. To clear a flooded engine, open
the throttle fully and continuously crank the engine. Do not pump the throttle as this will only
worsen the problem.
The ignition timing can also be set for cold cranking. As with the Cold Prime Map, the Crank
Ignition Map sets the ignition timing to be used while cranking according to the coolant
temperature. This Map is set flat to 15° at factory, but it can be adjusted to give better starting
at all temperatures.
7.2 Fuel Correction Versus Coolant Temperature
Once started, an engine requires more fuel when it is cold than when it is hot. This is a result
of low manifold and in-cylinder temperatures where fuel sticks to the walls and doesn't burn
properly. The Haltech system corrects for this by using the Fuel Coolant Map to define the
relation between engine temperature and extra fuel required. The E6K will automatically
reduce the amount of coolant correction applied to the engine as the throttle is opened and air
speed increases. The Fuel Coolant Map should not be adjusted until the Fuel Maps are
correctly tuned at operating temperature.
Access the Fuel Coolant Map from the Fuel Maps and Set-up Menu. The map defines the
percentage increase in fuel at any given engine temperature. The E6K is supplied with a