Refer to the Engine Mechanical and the Engine Performance diagnostic charts, for possible causes and
corrections of malfunctions. See
PERFORMANCE
. See
MECHANICAL
.
For fuel system diagnosis, refer to
Non-DTC Diagnostics/Driveability - Gas - Diagnosis and Testing
.
Additional tests and diagnostic procedures may be necessary for specific engine malfunctions that cannot be
isolated with the Service Diagnosis charts. Information concerning additional tests and diagnosis is provided
within the following:
Cylinder Compression Pressure Test: Refer to
CYLINDER COMPRESSION PRESSURE TEST
.
Cylinder Combustion Pressure Leakage Test: Refer to
CYLINDER COMBUSTION PRESSURE
LEAKAGE TEST
.
Engine Cylinder Head Gasket Failure Diagnosis: Refer to
CYLINDER HEAD GASKET
.
Intake Manifold Leakage Diagnosis: Refer to
INTAKE MANIFOLD LEAKS
.
Hydraulic Lash Adjuster Noise Diagnosis: Refer to
HYDRAULIC LIFTERS
.
Engine Oil Leak Inspection: Refer to
ENGINE OIL LEAK INSPECTION
.
PERFORMANCE
CONDITION
POSSIBLE CAUSE
CORRECTION
ENGINE WILL NOT START
1. Weak battery.
1. Test battery. Charge or replace
as necessary
Refer to
Electrical/Battery
System - Diagnosis and Testing
.
2. Corroded or loose battery
connections.
2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.
3. Faulty starter.
3. Test starting system. Refer to
Electrical/Starting - Diagnosis
and Testing
.
4. Faulty coil(s) or control unit.
4. Test and replace as needed.
(Refer to Appropriate Diagnostic
Information)
5. Incorrect spark plug gap.
5. Set gap. Refer to
Electrical/Ignition Control -
Specifications
.
6. Contamination in fuel system.
6. Clean system and replace fuel
filter.
7. Faulty fuel pump.
7. Test fuel pump and replace as
needed. (Refer to Appropriate
Diagnostic Information)
8. Incorrect engine timing.
8. Check for a skipped timing
belt/chain.
ENGINE STALLS OR IDLES
ROUGH
1. Idle speed too low.
1. Test minimum air flow. (Refer
to Appropriate Diagnostic
2010 Jeep Wrangler Sport
2010 ENGINE 3.8L - Service Information - Wrangler
viernes, 1 de octubre de 2021 05:18:29 p. m.
Page 2
© 2011 Mitchell Repair Information Company, LLC.
