GxT Ferret 54 ENGINE DIAGNOSTIC CENTER - Manual (Page 44)

POWER CONTRIBUTION — DIS and Distributor
Press POWER, SELECT Power Contribution , and press NEXT.
This test measures each cylinder’s contribution to the power output of the engine, without using
spark suppression.
Power Contribution is not available when Engine Setup "Ignition" is set to
Diesel .
To run this test on distributor engines, the black Primary Amps probe must be placed around
the wire supplying 12 volt power to the ignition coil(s) with the label facing toward the battery
feed.
There are two screens available. Press SELECT to change between screens.
The bar graph shows relative power contribution per cylinder:
OK п ь
Ω
ь я
π Ω
п
~ я я я я я я я я
LOW§§я§§я§§я§§я§§я§§я§§я§§я§§
Cyl 1 3 7 2 6 5 4 8
The other screen shows the variations numerically:
~ POWER CONTRIBUTION 190û
Power
Diff - 2 -14 2 1 - 1 - 0 1 0
Cyl 1 2 3 4 5 6 7 8
This test relies upon steady timing, fixed air-fuel feed, and a constant amount of engine drag
to make cylinder comparisons. To put a steady drag on the engine, turn the heater fan on high
and the headlights on bright. Keep the engine at idle RPM. However, if idle is surging, use a
throttle holder to bring it up to 1200. Low RPM gives better readings provided that RPM is
stable. Putting an engine in open loop mode may also help.
4-15