Will it hurt my Mercedes-Benz S420 to drive with old spark plugs?

Replace spark plugs on time or about every 30,000 miles or so. Without the spark of electricity created by spark plugs, your engine doesn’t have the combustion it needs to start — which could leave you stranded on the road. Always replace your spark plugs on time based on Mercedes-Benz’s recommendations.

What do I do if I see a pool of liquid under my Mercedes-Benz S420?

Puddles could indicate that your vehicle is leaking coolant, oil, or brake fluid. Ignoring these leaks can lead to permanent engine damage, so address these symptoms ASAP with a tune-up service.

What do hard starts and stops do to my S420 engine?

Hard starts and stops put extra wear and tear on engine components. Smooth, gradual starts and stops, on the other hand, are a great way to help your engine run better. They can also help maximize your fuel economy.

Where can I get a tune-up for my Mercedes-Benz S420?

At the nearest Firestone Complete Auto Care! We’re ready to help service, maintain, and repair your Mercedes-Benz S420.

How frequently do I need to get my Mercedes-Benz S420 fuel injectors cleaned?

The cleaning schedule for vehicle fuel injectors varies depending on your driving conditions and the type of fuel you use. Some manufacturers suggest cleaning your fuel system as part of routine maintenance, while others will recommend it on an as-needed basis if you’re experiencing poor performance. Reference your Mercedes-Benz owner’s manual for exact guidelines.

Who does Mercedes-Benz S420 tune-ups?

Visit your nearby Firestone Complete Auto Care for Mercedes-Benz S420 tune-ups and more. Schedule your appointment online and save big by checking out our latest offers.

1999 Mercedes-Benz S420 Tune-Up & Engine Service

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Schedule Mercedes-Benz S420 Tune-Up

Keep your S420 running newer, longer. Schedule an engine tune-up as soon as you notice your engine running differently. Make your appointment today.

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Enhance Mercedes-Benz S420 Performance with a Tune-Up

Is it time for an engine tune-up? If you're the type of driver who waits for something to go wrong with your vehicle, now is the time to work on that habit, particularly if you want to keep your 1999 Mercedes-Benz S420 in tip-top shape. Periodic tune-ups can bring more power back to your S420’s engine. Tune-ups give your engine a boost in efficiency, so you can enjoy improved fuel economy and lower emissions. When you follow the guidelines specified by Mercedes-Benz for your vehicle’s tune-up schedule, you invest in your S420's long-term health and engine performance.

Mercedes-Benz S420 Engine Tune-Up Services

Your local Firestone Complete Auto Care offers a range of engine tune-up services for your 1999 Mercedes-Benz S420. The standard Firestone Tune-Up is one service option. The standard Firestone Tune-Up includes new spark plugs (and installation!), a thorough inspection of engine components, and a lifetime parts warranty*. Another service option pays special attention to the filters in your S420. Specifically, we replace the fuel filter and air filter. Yet another service is a fuel system cleaning process, which involves removing varnish, dirt, and carbon deposits that have built up inside the fuel injectors, throttle body, and throttle plate in your S420. The result? Restored fuel system performance. Keep in mind that your S420's mileage and maintenance history can uniquely impact its tune-up needs. If you’re not sure what services are the best fit for your car, let us help! Chat with a Firestone technician before you jump into a specific service to ensure your engine tune-up money is well-spent.

Where to Get a Tune-Up for Your Mercedes-Benz S420

Come to Firestone Complete Auto Care for your next 1999 S420 engine tune-up. Consult your vehicle’s recommended service schedule from Mercedes-Benz, or make a service appointment if you notice any of these symptoms from your engine: shaking while the engine is idling, poor fuel economy, an illuminated check engine light on your dashboard, or a knocking sound when the engine is running.

*Talk to a Firestone Complete Auto Care teammate for full terms and conditions on warranties.

Common Engine Tune-Up Q&A For 1999 Mercedes-Benz S420s

Will it hurt my Mercedes-Benz S420 to drive with old spark plugs? Replace spark plugs on time or about every 30,000 miles or so. Without the spark of electricity created by spark plugs, your engine doesn’t have the combustion it needs to start — which could leave you stranded on the road. Always replace your spark plugs on time based on Mercedes-Benz’s recommendations.
What do I do if I see a pool of liquid under my Mercedes-Benz S420? Puddles could indicate that your vehicle is leaking coolant, oil, or brake fluid. Ignoring these leaks can lead to permanent engine damage, so address these symptoms ASAP with a tune-up service.
What do hard starts and stops do to my S420 engine? Hard starts and stops put extra wear and tear on engine components. Smooth, gradual starts and stops, on the other hand, are a great way to help your engine run better. They can also help maximize your fuel economy.
Where can I get a tune-up for my Mercedes-Benz S420? At the nearest Firestone Complete Auto Care! We’re ready to help service, maintain, and repair your Mercedes-Benz S420.
How frequently do I need to get my Mercedes-Benz S420 fuel injectors cleaned? The cleaning schedule for vehicle fuel injectors varies depending on your driving conditions and the type of fuel you use. Some manufacturers suggest cleaning your fuel system as part of routine maintenance, while others will recommend it on an as-needed basis if you’re experiencing poor performance. Reference your Mercedes-Benz owner’s manual for exact guidelines.
Who does Mercedes-Benz S420 tune-ups? Visit your nearby Firestone Complete Auto Care for Mercedes-Benz S420 tune-ups and more. Schedule your appointment online and save big by checking out our latest offers.

Proactive Maintenance - 1999 Mercedes-Benz S420

We know it’s not just a car, it’s your car. We’ll help you properly maintain your Mercedes-Benz S420 to keep it on the road and running smoothly. Learn more about maintenance below.

Repairs on Your 1999 Mercedes-Benz S420

Nothing lasts forever. Even your Mercedes-Benz S420's many parts and pieces. When something breaks, we're ready. Click on a repair below to learn more about 1999 Mercedes-Benz S420 repairs.