TEST
ACTION
APPLICABILITY
8
Turn the ignition off.
Note: Visually inspect the Crankshaft Position Sensor and related wire
harness connectors. Look for broken, bent, pushed out, or corroded termi-
nals.
Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Make sure the sensor mounting bolt(s) are tight.
Were any problems found?
All
Yes
→
Repair as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Go To
9
9
Turn the ignition off.
Disconnect and remove the crankshaft position sensor.
Inspect the tone wheel/flexplate slots for damage, foreign material, or excessive
movement.
Is the tone wheel/flexplate free from defects?
All
Yes
→
Go To
10
No
→
Repair/replace tone wheel/flex plate as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
10
If there are no possible causes remaining, view repair.
All
Repair
Replace the Crankshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
11
Turn the ignition off.
Visually inspect the related wire harness connectors. Look for broken, bent,
pushed out, or corroded terminals.
Visually inspect the related wiring harness. Look for any chafed, pierced,
pinched, or partially broken wires.
Note: Make sure the Camshaft Position Sensor and/or the Crankshaft
Position Sensor is tight.
Note: Refer to any technical service bulletins that may apply.
Were any problems found?
All
Yes
→
Repair as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Go To
12
12
Turn the ignition off.
With the DRBIII
t lab scope, back probe the CKP signal circuit at the PCM harness
connector using Miller special tool #6801.
Warning: Keep clear of the engine’s moving parts.
Start the engine.
Observe the lab scope screen while wiggling the wiring harness and connectors
related to the CKP sensor.
Were there any irregularities in the lab scope pattern when the wiggle test was
conducted?
All
Yes
→
Note where wiggling caused a missing CKP sensor signal. Repair
CKP sensor wiring as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Go To
13
172
DRIVEABILITY - GAS
P1391-INTERMITTENT LOSS OF CMP OR CKP —
Continued