Direct fire ignition sequence testing.
This type of installation is more difficult to setup and the following should be used to check
you have the correct ignition sequence for your engine.
In this example we are using a six cylinder engine with three double ended coils using
wasted spark. The firing order is 1,5,3,5,6,2,4
Coil pack 1 fires 1 & 6 cylinders.
Coil pack 2 fires 2 & 5 cylinders.
Coil pack 3 fires 3 & 4 cylinders.
Turn the engine until the piston is on compression TDC No1 cylinder, using a white marker
place a single mark on the harmonic balancer that will be visible with a timing light with the
engine cranking.
Turn the engine until it is on TDC of one of the cylinders that are on coil pack No2, and
place two marks on the harmonic balancer. Do the same for third coil pack, placing three
marks.
With the injector connectors disconnected or the fuel pump disconnected, use a timing light
connected to No1 spark plug, and crank the engine, you should see only one mark on the
harmonic balancer. If you see two or three marks you have the ignition output sequence
wrong. Swap the ignition output connectors in the SM4 harness connector or use the
software under Menu M1/Advanced Setup/Base angels (Ign) until you see one mark on the
balancer.
When this is correct put the timing light on the spark plug lead of the second cylinder to fire
and check for two marks on the balancer. If incorrect do the same as above. Repeat this
on cylinder three in the firing order, looking for three marks.
Example of using Advanced setup for correcting a wrong sequence wiring:-
Direct fire 4-cyl engine without wasted spark, under menu Base angles (Ign) it should read
0, 180, 360, 540, if output 2 & 3 are swapped you should have; 0, 360, 180, 540.
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