Mercedes-Benz 420SEL Ignition Cable (Spark plug wires) Replacement at your home or office.

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Ignition Cable (Spark plug wires) Replacement Service

How much does a Ignition Cable (Spark plug wires) Replacement cost?

On average, the cost for a Mercedes-Benz 420SEL Ignition Cable (Spark plug wires) Replacement is $393 with $155 for parts and $238 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1991 Mercedes-Benz 420SELV8-4.2LService typeIgnition Cable (Spark plug wires) ReplacementEstimate$574.32Shop/Dealer Price$662.74 - $903.88
1990 Mercedes-Benz 420SELV8-4.2LService typeIgnition Cable (Spark plug wires) ReplacementEstimate$559.00Shop/Dealer Price$642.16 - $879.37
Show example Mercedes-Benz 420SEL Ignition Cable (Spark plug wires) Replacement prices

What is the Ignition Cable (Spark plug wires) all about?

The ignition cables, also known as “spark plug wires” are part of the ignition system. They transfer the spark from the distributor or ignition coil to spark plugs that ignite the air-fuel mixture, starting the engine.

Over time, the cables can get weak and break down. This will make it harder for the spark to reach the engine cylinders, resulting in engine misfires. The car may not start at all. If one of the spark plugs has gone bad, the car will still start and run, but it will run poorly.

Keep in mind:

  • Ignition cable failure is often caused by other failing pieces in the ignition system; a mechanic should check for any other malfunctioning parts, and replace any parts of the system that don’t work.
  • Every time the ignition cables are replaced, the spark plugs should be inspected.
  • Leaking oil or coolant can cause ignition wire failure. If this is the case, the cause of the leak should be repaired or replaced, or else the new ignition wires will quickly be damaged as well.

How it's done:

  • Scan the computer system in the car for codes.
  • Inspect ignition cables (look for white spots).
  • Ohm test on individual cables.
  • Remove and replace the cables if found faulty.
  • Inspect the spark plugs.
  • Clear the codes.

Our recommendation:

Ignition wires should be replaced at least every 60,000 miles, but whenever your car is serviced, it’s a good idea to have the entire ignition system inspected. Any time that you have spark plugs replaced, it’s a good idea to have the ignition wires replaced as well. If you notice that your engine is running poorly, you should schedule an inspection.

What common symptoms indicate you may need to replace the Ignition Cable (Spark plug wires)?

  • Check Engine light is on.
  • Engine misfires.
  • Poor gas mileage.
  • Engine may shake (light vibration).

How important is this service?

The fuel in your automobile is ignited by a spark. This starts with the ignition coil, which transforms low voltage power into extremely high voltage. This high voltage is transferred through the ignition cables, and to the spark plug, where a spark is created that ignites the engine’s fuel, and powers the engine.

When one or more ignition cables fail, this voltage will not be transferred from the ignition coil to the spark plugs, and the fuel will not be ignited. Depending on how many of your ignition cables malfunction, your car will either run poorly, or won’t run at all.

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Excellent Rating

(13)

Rating Summary
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Marco

24 years of experience
157 reviews
Marco
24 years of experience
420SEL 1986 - Neutral Safety Switch - Riverside, CA
A life-saver

Carlos

23 years of experience
467 reviews
Carlos
23 years of experience
420SEL 1986 - Serpentine/Drive Belt - Ontario, CA
Carlos came on time (unlike others who cancelled the appointment several times). He came, TWICE because of my car needed more parts than expected. Great job, friendly, very professional, I HIGHLY recommend him, and will make sure next time - if needed - he will be the one I ask for. Thank you Carlos

Excellent Rating

(13)

Rating Summary
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Number of Mercedes-Benz 420SEL services completed
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