Will it hurt my Mercedes-Benz 420SEL 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 should I do if I see leaks under my 420SEL?

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 420SEL 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.

I need a Mercedes-Benz 420SEL tune-up. Where can I get on?

At your local Firestone Complete Auto Care! Our technicians know how to service, maintain, and repair Mercedes-Benz 420SELs.

How frequently do I need to get my Mercedes-Benz 420SEL 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 performs Mercedes-Benz 420SEL tune-ups?

When your 420SEL needs a tune-up, head to your local Firestone Complete Auto Care. Check out our latest offers to save on your service and schedule an appointment online.

1989 Mercedes-Benz 420SEL Tune-Up & Engine Service

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Schedule Mercedes-Benz 420SEL Tune-Up

Keep your 420SEL 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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Tune-Ups to Help Your Mercedes-Benz 420SEL Run Better

Is it time for an engine tune-up? If you tend to ignore your car until something goes wrong, now is the time to work on that habit, especially if you want your 1989 Mercedes-Benz 420SEL’s engine to last for a long time. Regular engine tune-ups can optimize your 420SEL’s power on the road. They're designed to help your engine start easier and run more efficiently, 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’re taking vital steps toward keeping your 420SEL’s engine running smoother, longer.

Routine Engine Tune-Up Service for Your Mercedes-Benz 420SEL

The Firestone Complete Auto Care location in your community offers several Mercedes-Benz 420SEL engine tune-up services. One option is the standard Firestone Tune-Up. 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 420SEL. 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 420SEL. This can improve your fuel system’s performance (and therefore, your engine’s performance). Here’s something to remember when choosing services: the mileage and service history of your 420SEL can determine what kind of service it needs. This means that a tune-up service that’s a great fit for another car may not be optimal for yours. Chat with a Firestone technician before you jump into a specific service to ensure your engine tune-up money is well-spent.

Where Should I Go for My Mercedes-Benz 420SEL Tune-Up?

Schedule your next 1989 420SEL engine tune-up service at Firestone Complete Auto Care. Follow Mercedes-Benz's recommended maintenance schedule or book an appointment as soon as you notice one of the following: stalling or shaky idling when you’re stopped, diminished fuel economy, knocking noises in the engine, or a lit up check engine light on your dashboard.

*Ask a Firestone Complete Auto Care teammate about full terms and conditions for warranties.

Questions About 1989 Mercedes-Benz 420SEL Engine Tune-Ups

Will it hurt my Mercedes-Benz 420SEL 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 should I do if I see leaks under my 420SEL? 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 420SEL 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.
I need a Mercedes-Benz 420SEL tune-up. Where can I get on? At your local Firestone Complete Auto Care! Our technicians know how to service, maintain, and repair Mercedes-Benz 420SELs.
How frequently do I need to get my Mercedes-Benz 420SEL 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 performs Mercedes-Benz 420SEL tune-ups? When your 420SEL needs a tune-up, head to your local Firestone Complete Auto Care. Check out our latest offers to save on your service and schedule an appointment online.

Maintenance for Your 1989 Mercedes-Benz 420SEL

Take care of your vehicle and it'll take care of you. Click on a service below to learn more about properly maintaining your Mercedes-Benz 420SEL.

1989 Mercedes-Benz 420SEL Repair

Nothing lasts forever. Even your Mercedes-Benz 420SEL's many parts and pieces. When something breaks, we're ready. Click on a repair below to learn more about 1989 Mercedes-Benz 420SEL repairs.