Tune-Up - Major

Complete major tune-up service for the 2008 Dodge Viper 8.4L V10, including spark plug replacement, ignition coil inspection, throttle body cleaning, air filter replacement, fuel filter replacement, PCV valve service, and comprehensive fluid inspection.

Warnings

Tools required

Parts

• Spark plugs (NGK or Champion copper core) × 10 — Use OEM specification - 10 required
• Engine air filter × 1 — Use OEM specification
• Fuel filter × 1 — Use OEM specification
• PCV valve × 1 — Use OEM specification
• PCV valve grommet × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and apply parking brake
2. Allow engine to cool completely for at least 2 hours after last operation
3. Disconnect negative battery cable and secure away from terminal
4. Remove engine cover by releasing the retention clips on each corner
5. Relieve fuel system pressure by removing fuel pump fuse and attempting to start engine until it stalls, then crank for 5 seconds
6. Place fender covers over both fenders to protect paint during service

Procedure

1. 1

   Remove engine air intake system
   Loosen the hose clamp securing the intake tube to the throttle body. Disconnect the MAF sensor electrical connector by pressing the tab and pulling straight out. Remove the air box mounting fasteners and lift the entire air intake assembly out of the engine bay. Inspect the intake tube for cracks or oil contamination.
2. 2

   Replace engine air filter
   Open the air box housing by releasing the spring clips on both sides. Remove the old air filter element and inspect the air box interior for debris or moisture. Clean the air box with a damp cloth if necessary. Install the new air filter element ensuring proper seating in the housing. Close and secure the air box clips.
3. 3

   Access and remove ignition coils - Bank 1 (driver side)
   Locate all five ignition coils on the driver side cylinder head. Disconnect each coil electrical connector by pressing the release tab. Remove the single fastener securing each coil pack (these are typically Torx or 8mm bolts). Carefully pull each coil straight up from the spark plug well. Inspect each coil for signs of carbon tracking, cracks, or oil contamination. Set aside for reinstallation if in good condition.
4. 4

   Remove and replace spark plugs - Bank 1 (driver side)
   Use compressed air or a clean cloth to remove any debris from around each spark plug well before removal. Using a 5/8" spark plug socket with appropriate extensions, remove all five spark plugs from Bank 1. Inspect each plug electrode and insulator for wear, carbon buildup, or abnormal coloring. Verify and set gap to the OEM specification for this engine; note that pre-gapped platinum plugs generally should not be re-gapped to avoid electrode damage. Do NOT apply anti-seize to the plug threads unless specifically required; most OEM plugs have a factory-applied coating and adding anti-seize will alter torque and risk overtightening in the aluminum heads. Hand-thread each new spark plug into the cylinder head to prevent cross-threading, then torque to the OEM specification (verify exact value in Mopar service documentation) using the torque wrench.
5. 5

   Access and remove ignition coils - Bank 2 (passenger side)
   Locate all five ignition coils on the passenger side cylinder head. Access may be more restricted on this side due to brake master cylinder and other components. Disconnect each coil electrical connector by pressing the release tab. Remove the single fastener securing each coil pack. Carefully pull each coil straight up from the spark plug well. Inspect each coil for signs of carbon tracking, cracks, or oil contamination.
6. 6

   Remove and replace spark plugs - Bank 2 (passenger side)
   Use compressed air or a clean cloth to remove any debris from around each spark plug well. Using a 5/8" spark plug socket with appropriate extensions (longer extensions may be needed for rear cylinders), remove all five spark plugs from Bank 2. Inspect each plug electrode and insulator for wear, carbon buildup, or abnormal coloring. Gap new spark plugs to OEM specification. Do NOT apply anti-seize to the plug threads unless specifically required; most OEM plugs have a factory-applied coating and adding anti-seize will alter torque and risk overtightening in the aluminum heads. Hand-thread each new spark plug into the cylinder head, then torque to specification using the torque wrench.
7. 7

   Reinstall ignition coils and reconnect
   Apply a thin coating of dielectric grease to the inside of each coil boot to prevent moisture intrusion and ensure easy future removal. Install each ignition coil by carefully aligning it with the spark plug terminal and pushing down firmly until fully seated. Install and tighten each coil mounting fastener. Reconnect all ten coil electrical connectors, ensuring each clicks into place securely.
8. 8

   Clean throttle body
   With the intake system removed, the throttle body is now accessible. Spray throttle body cleaner onto a clean microfiber towel and wipe the throttle plate and bore thoroughly to remove carbon deposits. Do NOT spray cleaner directly into the throttle body while the throttle plate is closed. This vehicle uses an electronic (drive-by-wire) throttle body; do NOT force the plate open by hand or expect it to open with key-ON. Clean only what is accessible with the plate at rest, or follow the OEM throttle relearn procedure after cleaning. Use a soft brush for stubborn deposits. Wipe clean with a dry towel.
9. 9

   Replace PCV valve
   Locate the PCV valve on the driver side valve cover (typically in a rubber grommet). Grasp the PCV valve firmly and twist while pulling upward to remove it from the grommet. If the grommet is damaged or brittle, remove and replace it as well. Install the new PCV valve by pressing it firmly into the grommet (or new grommet if replaced) until fully seated. Reconnect the PCV hose to the valve.
10. 10

    Replace fuel filter
    Verify whether a serviceable fuel filter exists — on the 2008 Viper the fuel filter is integrated into the in-tank fuel pump module and is not a standalone inline unit. If in-tank, replacement requires accessing the fuel pump module rather than an inline frame-rail filter.ointing toward engine) and secure in the mounting bracket. Reconnect both fuel lines, ensuring they click fully into place. Verify connections are secure by attempting to pull the lines off.
11. 11

    Inspect and top off all fluids
    Check engine oil level and condition - top off with 0W-40 full synthetic if needed. Inspect coolant level in the reservoir and top off with Mopar HOAT 50/50 coolant if low. Check brake fluid reservoir level and top off with DOT 4 if needed. Inspect power steering fluid reservoir and top off with the OEM-specified power steering fluid (verify exact Mopar specification) if low. Check manual transmission fluid level and top off with the OEM-specified manual transmission fluid (verify exact Mopar specification for the Viper T56) as needed. Inspect rear differential fluid level and condition.
12. 12

    Reinstall air intake system
    Position the air intake assembly back into the engine bay, ensuring all mounting points align. Install and tighten all air box mounting fasteners. Reconnect the MAF sensor electrical connector until it clicks. Slide the intake tube onto the throttle body and tighten the hose clamp securely. Verify all connections are secure and no tools or rags remain in the engine bay.
13. 13

    Reinstall engine cover and reconnect battery
    Position the engine cover over the engine and press down firmly on each corner until the retention clips engage with an audible click. Reconnect the negative battery cable to the battery terminal and tighten securely. Reinstall the fuel pump fuse to restore fuel system operation.

Reassembly

1. Ensure all electrical connectors are fully seated and secured
2. Verify all fasteners have been reinstalled and properly tightened
3. Confirm no tools or shop towels remain in the engine bay
4. Double-check that all fluid caps are reinstalled and tightened

Verification

• Turn ignition key to ON position (do not start) and listen for fuel pump priming - verify no fuel leaks at filter connections
• Start engine and allow to idle - listen for smooth operation and verify no misfires or rough running
• Rev engine gently to 2000-3000 RPM and verify smooth throttle response with no hesitation
• Check for any vacuum leaks (hissing sounds) around intake connections and PCV valve
• Allow engine to reach operating temperature and verify all gauges read normally
• Scan for diagnostic trouble codes using an OBD-II scanner - address any new codes that may have set
• Perform a test drive to verify improved throttle response and smooth acceleration through all RPM ranges
• Re-check all fluid levels after test drive and top off if necessary

More procedures for this vehicle