Haltech E6X Manual DOS Version - Manual (Page 67)

E6X Manual
67
Before starting the engine, go to the fuel map Range 1 (0 rpm), it is this map that the ECU
will use to calculate fuel requirements during cranking. The behaviour of fuel calculation
around cranking and idle differs depending on the type of load sensing used.
6.5.1 Starting the using Manifold Pressure Load Sensing
Try to start the engine. At cranking speeds the manifold pressure will be close to atmospheric
due to the low airflow around the throttle plate and through the idle passages. This means that
the ECU will use the bars at and just below atmospheric pressure. When the engine fires and
the engine speed starts to rise the vacuum developed in the manifold will increase due to the
increased airflow, the bars used for fuel calculation in this area will be further to the left of
those used at cranking. When the engine is at idle the manifold pressure should be fairly
steady, the bars used no should be further to the left again.
6.5.2 Starting the using Throttle Position Load Sensing
Try to start the engine. Starting the engine in throttle load sensing mode is easier since the
throttle stays closed, the bar that is used for calculation of fuel is the left most bar, When the
engine fires the speed will increase and the fuel requirement will change from the 0 rpm range
through to the appropriate idle range.
6.5.3 Useful Software Mapping features
It is important to identify the bars which affect the fuel or you could spend time adjusting the
wrong bars and upset fuelling under a totally different load or speed condition.
A useful tool for identifying the active fuel bar is the small red arrow (called the map pointer)
that points to the current bar in the map the ECU is using for fuel calculations as shown
below.