Tune-Up - Minor

Minor tune-up service for the 2008 Dodge Viper 8.4L V10 including spark plug replacement, ignition coil inspection, air filter replacement, throttle body cleaning, and general ignition system service.

Warnings

Tools required

Parts

• Spark plugs × 10 — NGK ZFR5N or equivalent iridium plug, 0.050" gap
• Engine air filter × 1 — Mopar 4861358AA or equivalent

Preparation

1. Ensure engine is completely cold to the touch.
2. Park vehicle on level surface and engage parking brake.
3. Open hood and secure in fully open position.
4. Disconnect negative battery cable to prevent accidental starter engagement.
5. Remove engine cover by lifting from the front and sliding forward to disengage rear mounting tabs.
6. Take photos of ignition coil positions and wire routing for reference during reassembly.

Procedure

1. 1

   Remove air intake system
   Disconnect the mass airflow sensor electrical connector by pressing the release tab. Loosen the hose clamps at the throttle body and air box using a flat screwdriver or 7mm socket. Remove the intake tube assembly by lifting it out of the engine bay. Disconnect any breather hoses attached to the intake tube.
2. 2

   Remove and replace engine air filter
   Open the air box by releasing the spring clips on each side of the housing. Lift the air box cover and remove the old air filter element. Inspect the air box for debris and clean if necessary using compressed air or a clean towel. Install the new air filter element, ensuring it seats properly in the housing. Secure the air box cover with the spring clips until they click into place.
3. 3

   Access and inspect ignition coils - passenger side bank
   The Viper uses individual coil-on-plug ignition coils for each cylinder. Starting with the passenger side bank (verify cylinder numbering per factory documentation for 2008 Viper 8.4L V10), disconnect the electrical connector from each coil by pressing the release tab and pulling straight up. Remove the mounting bolt from each coil (typically one bolt per coil). Carefully wiggle and pull each coil straight up to remove it from the spark plug well. Inspect each coil for cracks, carbon tracking, or oil contamination. Set coils aside in order.
4. 4

   Remove and replace spark plugs - passenger side bank
   Use compressed air to blow out any debris from around each spark plug before removal. Using the spark plug socket with appropriate extensions, carefully loosen each spark plug 1-2 turns initially to ensure they are not seized. Once confirmed free, remove all 5 spark plugs from the passenger bank. Inspect old plugs for unusual wear patterns, oil fouling, or incorrect gap. Check the gap on new spark plugs with gap tool and confirm 0.050" specification. Do not apply anti-seize unless specified by the plug manufacturer, as most modern plated plugs are designed for dry installation. Hand thread each new spark plug carefully to avoid cross-threading. Torque spark plugs to the factory specification (verify exact value for 2008 Viper 8.4L V10).
5. 5

   Reinstall ignition coils - passenger side bank
   Apply a thin coat of dielectric grease to the inside of each ignition coil boot where it contacts the spark plug terminal. Carefully insert each coil back into its spark plug well, ensuring it seats fully onto the spark plug. Install the coil mounting bolt and tighten to the factory specification (verify exact value; small M6 coil bolts are typically around 7 lb-ft). Reconnect the electrical connector to each coil, ensuring it clicks into place.
6. 6

   Access and inspect ignition coils - driver side bank
   Move to the driver side bank (verify cylinder numbering per factory documentation for 2008 Viper 8.4L V10). Disconnect the electrical connector from each coil by pressing the release tab and pulling straight up. Remove the mounting bolt from each coil. Carefully wiggle and pull each coil straight up to remove it from the spark plug well. Note that rear cylinders on this bank may require more maneuvering due to master cylinder and brake booster proximity. Inspect each coil for cracks, carbon tracking, or oil contamination. Set coils aside in order.
7. 7

   Remove and replace spark plugs - driver side bank
   Use compressed air to blow out any debris from around each spark plug before removal. The rear-most plugs will require longer extensions and possibly a swivel socket for access. Using the spark plug socket with appropriate extensions, carefully loosen each spark plug 1-2 turns initially to ensure they are not seized. Once confirmed free, remove all 5 spark plugs from the driver bank. Inspect old plugs for unusual wear patterns, oil fouling, or incorrect gap. Check the gap on new spark plugs with gap tool and confirm 0.050" specification. Do not apply anti-seize unless specified by the plug manufacturer, as most modern plated plugs are designed for dry installation. Hand thread each new spark plug carefully to avoid cross-threading. Torque spark plugs to the factory specification (verify exact value for 2008 Viper 8.4L V10).
8. 8

   Reinstall ignition coils - driver side bank
   Apply a thin coat of dielectric grease to the inside of each ignition coil boot where it contacts the spark plug terminal. Carefully insert each coil back into its spark plug well, ensuring it seats fully onto the spark plug. Install the coil mounting bolt and tighten to the factory specification (verify exact value; small M6 coil bolts are typically around 7 lb-ft). Reconnect the electrical connector to each coil, ensuring it clicks into place.
9. 9

   Clean throttle body
   With the intake tube removed, access to the throttle body is clear. Spray throttle body cleaner onto a clean microfiber towel (never spray directly into the throttle body with the engine off and butterfly closed, as this can damage the coating). Gently wipe the throttle plate and bore, removing carbon deposits. Do not force the throttle plate open excessively. For the back side of the throttle plate, carefully open it by hand while cleaning. Use a dry towel to remove any excess cleaner. Allow throttle body to air dry for 2-3 minutes.
10. 10

    Reinstall air intake system
    Reconnect any breather hoses to the intake tube. Position the intake tube into the engine bay, seating it onto the throttle body and air box connections. Tighten both hose clamps securely, ensuring even pressure around the circumference. Reconnect the mass airflow sensor electrical connector until it clicks.
11. 11

    Reinstall engine cover and reconnect battery
    Position the engine cover by engaging the rear mounting tabs first, then pressing down at the front until it clicks into place. Reconnect the negative battery cable and tighten the terminal clamp securely. Close the hood.

Reassembly

1. Double-check that all ignition coil electrical connectors are fully seated and locked.
2. Verify all tools and parts have been removed from the engine bay.
3. Confirm air intake system is properly secured with no loose connections.

Verification

• Turn the ignition to the ON position (without starting) and verify no check engine light or warning messages appear immediately.
• Start the engine and listen for smooth, even idle with no misfires or rough running.
• Allow engine to idle for 2-3 minutes, monitoring for any abnormal sounds, vibrations, or warning lights.
• Rev the engine gently to 2000-3000 RPM and verify smooth throttle response.
• Check for any fuel, vacuum, or oil leaks around the work area.
• If a check engine light appears, use a scan tool to check for misfire codes indicating improper installation.
• Take a short test drive to verify normal acceleration and no hesitation or stumbling under load.
• The throttle body may need to relearn idle position; if idle is rough initially, allow the engine to idle for 5-10 minutes or perform a throttle relearn procedure using a scan tool if available.

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle