Dodge ZB 2005 Service Manual page 1216

P0300-MULTIPLE CYLINDER MIS-FIRE —
TEST
11 Turn the ignition off.
Disconnect the PCM harness connectors.
Check the Injector Control circuit for an open, short to ground, and short to voltage.
Was a problem found with the Injector Control circuit?
Yes → Repair the excessive resistance or short in the Injector Control
→ Go To 17
No
12 Turn the ignition off.
Warning: The fuel system is under a constant pressure (even with the engine
off). Before testing or servicing any fuel system hose, fitting or line, the fuel
system pressure must be released.
Raise vehicle on hoist, and disconnect the fuel pressure line at the fuel pump module.
Install special tool #6539 (5/16 ) #6631(3/8 ) fuel line adapter and the fuel pressure
gauge between the fuel supply line and the fuel pump module.
Ignition on, engine not running.
With the DRBIII , actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 379 KPa +/- 14 KPa (55 psi +/- 2 psi).
Is the fuel pressure within specification?
Yes → Repair or replace fuel supply line as necessary.
→ Go To 13
No
13 Turn the ignition off.
Warning: The fuel system is under a constant pressure (even with the engine
off). Before testing or servicing any fuel system hose,fitting or line, the fuel
system pressure must be released.
Remove the Fuel Pump Module and inspect the Fuel Inlet Strainer.
Is the Fuel Inlet Strainer plugged?
Yes → Replace the Fuel Pump Inlet Strainer.
→ NOTE: Before continuing, check the Fuel Pump Module harness
No
14 Turn the ignition off.
Remove the ignition wire.
Measure the resistance of the ignition wire.
Is the resistance below 10K ohms?
Yes → Go To 15
→ Replace the Ignition Wire.
No
ACTION
circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
connector terminals for corrosion, damage, or terminal push out.
Ensure the ground circuit is operating properly. Repair as neces-
sary. Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
DRIVEABILITY - GAS
Continued
95
APPLICABILITY
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All
All
All