Haltech E6A - Manual (Page 59)

59
Chapter 7
Cold Starting and Running
The Haltech E6A 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 E6A 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 Setup 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 E6A 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.