Haltech F9A - Manual (Page 53)

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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 F9 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 no be adjusted until the Fuel Maps are correctly
tuned at operating temperature.
Access the Fuel Coolant Map from the Fuel Maps and Setup Menu. The map defines the
percentage increase in fuel at any given engine temperature. The F9 is supplied with a default
coolant map which may not need to be modified. If the coolant map requires modification, the
changes should be done Online and while the engine is warming. Start the cold engine and
adjust the Fuel Coolant Map so that the engine idles evenly. You should not touch the throttle
while adjusting this map. Follow the arrow as the engine warms to provide good running
mixtures up to operating temperature, where there should be zero coolant correction.