Haltech E6K User Manual
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Method 2
Method 2 is similar to Method 3 as it uses a constant value as the barometric pressure but
Method 2 is restricted only to engine mapped via the MAP sensor. The other difference is the
way it gets this barometric pressure value. In Method 3 you are required to enter a value as the
Barometric Pressure and the E6K will lock to it. Method 2 requires you to open the throttle
butterfly and force the manifold to contain the same pressure as the ambient environment
which will be read by the MAP sensor and used by the E6K.
When the E6K is powered on, it will run a small test to determine the barometric pressure. As
you should have read earlier, the ECU switches the fuel pump on at start up (fuel pump
prime). If the engine is not started, the fuel pump will be switched off. At this time, the ECU
also reads the MAP Sensor. If the engine is not running, the MAP sensor will indicate the
prevailing barometric pressure. The ECU remembers this pressure and uses it to perform a
barometric correction on the fuel delivery.
If at start up the engine is cranked before the fuel pump prime has finished the ECU cannot
read the barometric pressure from the MAP sensor as the engine will be applying a vacuum to
it. In this case, the E6K will use the pressure value as set in Method 3. If you have not
adjusted it from factory settings, this will be 1013 mBars. To complete Method 2 follow these
steps:
1.
Firstly set the Barometric Lock in the Fuel Set-up page to “disabled”.
2.
Make sure the throttle position sensor is properly calibrated. It must exceed 96%
throttle for this to work. Also make sure that the MAP Sensor is set correctly in the
Identification.
3.
Switch the ignition off.
4.
Apply full throttle.
5.
Switch the ignition on but DO NOT crank the engine.
6.
Wait till the fuel pump prime finishes (about 5 seconds) then release the throttle.
The current barometric pressure as read by the MAP Sensor will be programmed
into the ECU’s memory.
It is not necessary or advisable to perform this reset regularly. It should only be done if
the vehicle’s regular place of garage is moved or if problems are suspected in the barometric
correction. For example, if an engine is tuned at sea level but is intended to be used mainly at
a higher altitude, then the reset should be performed once it reaches its new regular location.
After that, the automatic reading done at start up will be sufficient for the E6K to apply
barometric compensation and Method 2 is complete.