When to replace the Spark Plug on your MERCEDES-BENZ S-CLASS
Recommended replacement interval for the part category Spark plug : 18 month / 30000 km
Important!
This replacement procedure can be used for:
MERCEDES-BENZ S-Class Saloon (W140) S 280 (140.028), MERCEDES-BENZ S-Class Saloon (W140) 300 SE 2.8 (140.028), MERCEDES-BENZ S-Class Saloon (W140) 300 SE, SEL/S320 (140.032, 140.033) View more

The steps may slightly vary depending on the car design.

This video shows the replacement procedure of a similar car part on another vehicle

Tools
Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Tools you might need:
Electronic spray
High-temperature anti-seize lubricant
Torque wrench
Torx bit T30
Spark plug socket # 16
Ratchet wrench
Long round nose pliers
Microfibre towel
Fender cover
Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Professionals recommend:
  • The replacement procedure is the same for all spark plugs.
  • All work should be done with the engine stopped.
Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Take the following steps:
  1. Step 1
    Open the hood.
    Step 2
    Use a fender protection cover to prevent damaging paintwork and plastic parts of the car.
    Step 3
    How to change Spark Plug on W140 1991 - free PDF and video manuals
    Remove the engine cover.
    AUTODOC recommends:
    Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Do not use excessive force when removing the part as this may damage it.
  2. Step 4
    How to replace MERCEDES-BENZ S-Class Saloon (W140) 300 SE, SEL/S320 (140.032, 140.033) 1992 Spark Plug - step-by-step manuals and video guides
    Remove the air intake hoses.
  3. Step 5
    W140 S 350 3.5 Turbo Diesel (140.134) 1993 Spark Plug replacement: free workshop manuals
    Clean the air filter cover and housing.
    Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Tip:
    Before cleaning the air filter cover and housing, cover the air duct parts, mass airflow sensor (if available), throttle valve with a clean cloth.
  4. Step 6
    Changing Spark Plug on MERCEDES-BENZ S-Class Saloon (W140) 500 SE, SEL (140.050, 140.051) 1994 by yourself
    Remove the air filter housing.
    AUTODOC recommends:
    Do not apply excessive force when removing the part. Otherwise you may damage it.
  5. Step 7
    How to remove MERCEDES-BENZ S-CLASS S 500 5.0 (140.050, 140.051) 1995 Spark Plug - online easy-to-follow instructions
    Cover the throttle body with a microfibre towel to prevent dust and dirt from getting into the system.
  6. Step 8
    How to replace Spark Plug on MERCEDES-BENZ S-Class Saloon (W140) 1996: download PDF manuals and video instructions
    Unplug the connectors from the ignition coils.
  7. Step 9
    How hard is it to do yourself: Spark Plug replacement on W140 400 SE, SEL/S420 (140.042, 140.043) 1997 - download illustrated guide
    Remove the spark plug wire connectors from the spark plug wells. Use long round nose pliers.
    Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Tip from AUTODOC:
    Be careful to avoid damaging spark plug wires.Remember the sequence of the spark plug wires connectors.
  8. Step 10
    Need to know how to renew Spark Plug on MERCEDES-BENZ S-CLASS 1998? This free workshop manual will help you to do it yourself
    Unscrew the fasteners of the ignition coils. Use Torx T30. Use a ratchet wrench.
  9. Step 11
    Changing of Spark Plug on W140 1991 won't be an issue if you follow this illustrated step-by-step guide
    Take out the ignition coil from the spark plug well.
    Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. AUTODOC experts recommend:
    Remember the sequence of steps for ignition coil demounting.
  10. Step 12
    MERCEDES-BENZ S-CLASS S 420 (140.042, 140.043) Spark Plug replacement: online guides and video tutorials
    Clean dirt, dust and debris from inside the spark plug wells.
  11. Step 13
    Replacing Spark Plug on W140 1993 300 SE, SEL/S320 (140.032, 140.033) by yourself
    Unscrew the spark plugs. Use the spark plug socket #16. Use a ratchet wrench.
  12. Step 14
    S-Class Saloon (W140) S 500 5.0 (140.050, 140.051) 1994 Spark Plug DIY replacement workshop manual
    Take out the spark plugs.
  13. Step 15
    How to change Spark Plug on MERCEDES-BENZ S-Class Saloon (W140) 1995 - tips and tricks
    Apply a thin layer of a special high temperature anti-seize lubricant to the threads of the new spark plugs.
  14. Step 16
    Step-by-step recommendations for DIY replacement W140 1996 S 500 5.0 (140.050, 140.051) Spark Plug
    Install the new spark plugs into their mounting seats.
  15. Step 17
    DIY replacement of Spark Plug on MERCEDES-BENZ S-Class Saloon (W140) S 300 3.0 Turbo Diesel (140.135) 1997 is not an issue anymore with our step-by-step tutorial
    Screw new spark plugs and tighten them. Use the spark plug socket #16. Use a torque wrench. Tighten it to 27 nm torque.
    Replacement: spark plugs – MERCEDES-BENZ S-CLASS (W140) V6. Professionals recommend:
    Don't tighten the plugs with excessive force. Exceeding tightening torque can damage the thread connection. Be careful when working with a spark plug wrench. Its skewing can cause damage to the threaded connection.
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DIY MERCEDES-BENZ S-Class Saloon (W140) Spark Plug replacement - online guide
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