Diagnosis And Testing; Diagnosis And Testing - Engine; Diagnosis - Introduction; Diagnosis And Testing - Engine Performance - Chrysler Pacifica 2004 Service Manual

CS
ENGINE 3.5L (Continued)

DIAGNOSIS AND TESTING

DIAGNOSIS AND TESTING - ENGINE

DIAGNOSIS - INTRODUCTION

Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
Refer to Service Diagnosis—Mechanical Chart and
Service Diagnosis—Performance Chart, for possible
causes and corrections of malfunctions. Refer to
FUEL SYSTEM for the fuel system diagnosis.

DIAGNOSIS AND TESTING - ENGINE PERFORMANCE

CONDITION
ENGINE WILL NOT START
ENGINE STALLS OR IDLES
ROUGH
Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can-
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following:
• Cylinder Compression Pressure Test
• Cylinder Combustion Pressure Leakage Test
• Cylinder Head Gasket Failure Diagnosis
• Intake Manifold Leakage Diagnosis
• Lash Adjuster (Tappet) Noise Diagnosis
• Engine Oil Leak Inspection
POSSIBLE CAUSE
1. Weak battery.
2. Corroded or loose battery
connections.
3. Faulty starter.
4. Faulty coil(s) or control unit.
5. Incorrect spark plug gap.
6. Contamination in fuel system.
7. Faulty fuel pump.
8. Incorrect engine timing.
1. Idle speed too low.
2. Incorrect fuel mixture.
3. Intake manifold leakage.
4. Faulty coil(s).
ENGINE 9 - 5
CORRECTION
1. Test battery. Charge or replace
as necessary. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/
BATTERY - DESCRIPTION)
2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.
3. Test starting system. (Refer to 8 -
ELECTRICAL/STARTING -
DIAGNOSIS AND TESTING)
4. Test and replace as needed.
(Refer to Appropriate Diagnostic
Information)
5. Check and adjust gap as needed.
6. Clean system and replace fuel
filter.
7. Test fuel pump and replace as
needed. (Refer to Appropriate
Diagnostic Information)
8. Check for a skipped timing belt or
a loose camshaft sprocket.
1. Test minimum air flow. (Refer to
Appropriate Diagnostic Information)
2. (Refer to Appropriate Diagnostic
Information)
3. Inspect intake manifold gasket,
manifold, and vacuum hoses.
4. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)