Haltech F9A - Manual (Page 69)

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A.8 Cold Running Problems
If the engine idles poorly when cold then the coolant map may need adjusting. If the engine is
hunting slightly when cold, then the coolant correction map is just too lean, and so needs a
small amount of enrichment. Slight advance with the coolant temp. can help. If the engine is
difficult to drive when cold, particularly with gear changes, try increasing the coolant
correction factor for the throttle pump.
An engine that will idle when warm, but fails to idle cold unless a tiny amount of throttle is
applied may require idle speed control, with a fast-idle function for when the engine is cold.
The F9A (optional upgrade from F9) can control an Idle Air Control motor to perform this
function.
A.9 Fuel Consumption
Poor fuel consumption is a result of a too rich mixture. If the fuel consumption in traffic is
poor but the highway consumption is good, then it could be the areas of the map used for
accelerating that need to be leaned out. The throttle pump may also waste fuel if its values are
too high. Also try using the fuel cutoff on deceleration feature.
If the city consumption is fair but highway cruising uses too much fuel then lean out the light
load bars on the 2000 rpm to 3000 rpm maps (This is where most cruising takes place).
If the cold start map is supplying too much fuel on warm-up this will also affect the fuel
consumption of the vehicle.