Fuel Injection System
8.20
Fichtâ Fuel Injection System -- Action Steps -- Fuel System / Fuel Injectors
NOTE: Remember these important facts regarding the fuel injectors:
S During cranking, Vdc should “step--up” from 12V, to 22V. If this does not occur, check the stator
and/or EMM regulator/rectifier .
S During normal operation, each injector should receive 39--45Vdc. Furthermore, ANY W/RED
wire in the electrical system should show 39--45 Vdc. If voltage is either too high or too low, check
stator output and resistance along with the EMM regulator/rectifier.
S Use an inductive timing light on each injector lead to verify operation during cranking and normal
operation.
S Always check the wiring harnesses for shorts, loose wires, loose pins, and pinched wires.
S If voltage to other injector(s) increases during cranking when one injector is disconnected from
the harness, test the stator for output and resistance along with the EMM regulator/rectifier.
S A “hotter” than average fuel injector may indicate that its circuit is shorted out. Symptoms of this
include: fouled spark plugs and rich--runability problems. TEMPORARILY swapping injectors
from one cylinder to another may reveal circuit failures.
S Always verify, using the diagnostic software, that the serial numbers encoded on the EMM match
that of each injector.
S An audible “clicking” sound should be heard when testing injectors using the diagnostic software.
Fichtâ Fuel Injection System -- Action Steps -- Ignition System
If fault is suspected with the ignition system, f o llo w these steps:
1. Visually inspect all engine grounds. Resistance across all grounds should read 0 ohms.
2. Check for disconnected wires and/or cracked ignition coils.
3. Perform a cranking spark test. Connect an inductive timing light to individual leads. Insert lanyard in stop /
start switch, and turn over engine. If spark is found on all ignition coils, and high tension leads, but engine will
not start, proceed with next test.
4. If spark is present, but engine either will not start or backfires, verify that the flywheel key is not sheared. Bring
the MAG piston to TDC. Remove the CPS from the stator housing. There should be 3 encoder ribs showing
through the hole with the center rib straight up and down. You can also very timing by removing the plug from
the front of the flywheel cover . Using a mirror, verify that the first line is showing when the MAG piston is at
TDC.
5. Test the stator for cranking output and resistance. Test the EMM regulator/rectifier. Connect the SUSPECT 8
and 12 pin harnesses to a known good EMM. Leave the 40 pin harness connected to the SUSPECT EMM.
Attempt to start the engine. If engine starts, first check all connections. Replace EMM if no problems with the
connections are found.
6. Verify crank position sensor resistance and wire connections.
7. Verify that the battery is fully charged and all connections are clean and tight.
8. Verify that voltage on ALL RED/PUR circuits does not drop below 9.5 Vdc while cranking. During operation,
ALL RED/PUR circuits should read a minimum of 12.5 Vdc.
9. Test for voltage drop and current draw on the starter motor circuit. Please refer to the Electrical Chapter for
further information.
10. Using the diagnostic software, monitor the alternator output voltage. At idle, 39--45Vdc should be showing.
11. Visually inspect the spark plugs for correct gap, heat range, and for cracked or loose insulators.
12. Check the capacitor. Monitor voltage after you remove the lanyard. If voltage bleeds to 0V, the capacitor is ok.
If the voltage immediately drops to 0, replace the capacitor.
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