What happens if my Mercedes-Benz 420SEL spark plugs fail?

When it’s time to replace the spark plugs, don’t delay. These small (but vital!) parts provide the electric spark that your car needs in order to start, and old spark plugs can prevent your car from starting at all. Replace spark plugs on time or about every 30,000 miles or so.

What do I do if I see a pool of liquid under my Mercedes-Benz 420SEL?

Don't ignore puddles of fluid under your Mercedes-Benz 420SEL. It could signal a coolant leak, brake fluid leak, or an oil leak. Let any one of these leaks linger and it could cause engine damage.

Are some driving habits better for my Mercedes-Benz 420SEL engine than others?

Hard stops and starts can lead to premature wear on your engine’s components. Lighten up that lead foot and opt for steady, fluid starts and stops instead. Your engine (and your passengers!) will thank you.

Where can I get a tune-up for my Mercedes-Benz 420SEL?

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

How often do Mercedes-Benz 420SEL fuel injectors need to be cleaned?

There is no hard and fast rule on how often fuel injectors should be cleaned, and it can vary based on driving habits and fuel type. Some manufacturers may suggest including a fuel system cleaning in your regular maintenance schedule. Or you may need to clean your fuel injectors as needed if you notice signs of a fuel system problem.

Who does 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.

1991 Mercedes-Benz 420SEL Tune-Up & Engine Service

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Schedule Your Mercedes-Benz 420SEL Tune-Up Service Appointment

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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Enhance Mercedes-Benz 420SEL 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, especially if you drive a 1991 Mercedes-Benz 420SEL. Regular engine tune-ups can optimize your 420SEL’s power on the road. Tune-ups help your engine start smoothly and run efficiently, so you can enjoy improved fuel economy and lower emissions. When you take your car for regular engine tune-ups as recommended by Mercedes-Benz, you’re taking vital steps toward keeping your 420SEL’s engine running smoother, longer.

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

Your local Firestone Complete Auto Care offers a range of engine tune-up services for your 1991 Mercedes-Benz 420SEL. The first is the standard Firestone Tune-Up. This includes the installation of new spark plugs and a visual inspection of your engine’s components, plus a lifetime warranty on parts*. A second service option replaces the air and fuel filter in your 420SEL. The third tune-up option is a fuel system cleaning service, which is a three-step process that removes varnish, dirt, and carbon deposits on your 420SEL's fuel injectors, throttle body, and throttle plate. This can improve your fuel system’s performance (and therefore, your engine’s performance). Keep in mind that your 420SEL's mileage and maintenance history can uniquely impact its tune-up needs. This means that a tune-up service that’s a great fit for another car may not be optimal for yours. Ask one of our technicians what your vehicle needs, based on your driving habits and your car’s current condition.

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

If you’re looking for 1991 420SEL engine tune-up services, head to Firestone Complete Auto Care. 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: decreased gas mileage, "rough" idling or stalling when stopped, knocking noises in the engine, or a lit up check engine light on your dashboard.

*Check with a teammate at Firestone Complete Auto Care for complete terms and conditions regarding warranties.

1991 Mercedes-Benz 420SEL Engine Tune-Up Q&A

What happens if my Mercedes-Benz 420SEL spark plugs fail? When it’s time to replace the spark plugs, don’t delay. These small (but vital!) parts provide the electric spark that your car needs in order to start, and old spark plugs can prevent your car from starting at all. Replace spark plugs on time or about every 30,000 miles or so.
What do I do if I see a pool of liquid under my Mercedes-Benz 420SEL? Don't ignore puddles of fluid under your Mercedes-Benz 420SEL. It could signal a coolant leak, brake fluid leak, or an oil leak. Let any one of these leaks linger and it could cause engine damage.
Are some driving habits better for my Mercedes-Benz 420SEL engine than others? Hard stops and starts can lead to premature wear on your engine’s components. Lighten up that lead foot and opt for steady, fluid starts and stops instead. Your engine (and your passengers!) will thank you.
Where can I get a tune-up for my Mercedes-Benz 420SEL? At your local Firestone Complete Auto Care! Our technicians know how to service, maintain, and repair Mercedes-Benz 420SELs.
How often do Mercedes-Benz 420SEL fuel injectors need to be cleaned? There is no hard and fast rule on how often fuel injectors should be cleaned, and it can vary based on driving habits and fuel type. Some manufacturers may suggest including a fuel system cleaning in your regular maintenance schedule. Or you may need to clean your fuel injectors as needed if you notice signs of a fuel system problem.
Who does 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 1991 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.

Repair Service for Your 1991 Mercedes-Benz 420SEL

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 1991 Mercedes-Benz 420SEL repairs.