Dodge Nitro. Manual - part 66

2007 ENGINE

4.0L - Service Information - Nitro 

DESCRIPTION 

4.0L ENGINE 

Fig. 1: 4.0L ENGINE 
Courtesy of CHRYSLER LLC 

The 4.0L Liter (244 Cubic Inches) 60° V-6 engine is a single overhead camshaft design with hydraulic lifters 
and four valves per cylinder The engine does not have provisions for a free wheeling valve train. See Fig. 1.

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

Fig. 2: Cylinder Numbering & Firing Order 
Courtesy of CHRYSLER LLC 

The cylinders are numbered from front to rear, with the right bank odd numbered, and the left bank even 
numbered The firing order is 1-2-3-4-5-6. See Fig. 2.

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

Fig. 3: Engine Identification 
Courtesy of CHRYSLER LLC 

The engine identification number (2) is located on the rear of engine block just below the left cylinder head (1). 
See Fig. 3. 

DIAGNOSIS AND TESTING 

INTRODUCTION 

1 - REAR OF LEFT CYLINDER HEAD
2 - ENGINE IDENTIFICATION NUMBER

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

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 ENGINE MECHANICAL and ENGINE PERFORMANCE for possible causes and corrections of 
malfunctions. Refer to FUEL SYSTEM for the fuel system diagnosis.  

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  

Cylinder Combustion Pressure Leakage Test  

Cylinder Head Gasket Failure Diagnosis  

Intake Manifold Leakage Diagnosis  

Lash Adjuster (Tappet) Noise Diagnosis  

Engine Oil Leak Inspection  

ENGINE MECHANICAL 

CONDITION 

POSSIBLE CAUSES 

CORRECTION 

NOISY VALVES

1. High or low oil level in 
crankcase.

1. Check and correct engine oil 
level.

2. Thin or diluted oil.

2. Change oil to correct viscosity.

3. Thick oil

3. (a.) Change oil and filter.

 

(b.) Run engine to operating 
temperature.

 

(c.) Change oil and filter again.

4. Low oil pressure.

4. Check and correct engine oil 
level.

5. Dirt in tappets/lash adjusters.

5. Replace rocker arm/hydraulic 
lash adjuster assembly.

6. Worn rocker arms.

6. Inspect oil supply to rocker 
arms.

7. Worn tappets/lash adjusters.

7. Install new rocker 
arm/hydraulic lash adjuster 
assembly.

8. Worn valve guides.

8. Replace cylinder head(s).

9. Excessive runout of valve seats 
on valve faces.

9. Grind valve seats and valves.

10. Missing adjuster pivot.

10. Replace rocker arm/hydraulic 
lash adjuster assembly.

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro