Why does the check engine light come on when I start my S420?

Generally, your check engine light turning on upon ignition is not a bad thing. This is just your S420 testing its circuits. The dash light shouldn't stay on. If it does, you might want to bring your vehicle in for service.

Why does my Mercedes-Benz engine sound different?

Strange under-the-hood noises can point to problems within your Mercedes-Benz S420 engine. Tapping or knocking could mean you're low on oil. Whistling sounds could mean you have an intake leak or misaligned belt. Squealing can be traced back to a loose fan belt, and grinding might be a sign of brake problems rather than engine issues.

What could damage my Mercedes-Benz S420 engine?

Certain driving habits can damage your engine and should be avoided. These habits include 'running on fumes,' flooring the gas pedal while the car is in Park, or accelerating too quickly, too soon. Help sustain your engine’s performance and efficiency by staying miles away from these bad driving practices.

Is it okay to put water in my Mercedes-Benz S420 radiator?

Only in emergencies. A 50/50 mix of coolant and water (or a pre-mixed) coolant is recommended. However, if you must keep driving when you're out of coolant, it's better to drive with water in your coolant reservoir than nothing.

What can cause a S420 engine to suddenly stop?

Your S420 car engine could stop suddenly due to low fuel, electrical issues, overheating, a faulty ignition system, mechanical troubles, or sensor problems.

Who fixes Mercedes-Benz S420 engines?

For Mercedes-Benz S420 engine repair, trust your local Firestone Complete Auto Care. You can make an appointment today at any of our thousands of locations across the U.S.

1999 Mercedes-Benz S420 Engine Repair

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1999 Mercedes-Benz S420 Trim Options

Select your Mercedes-Benz S420 trim level to learn more about Mercedes-Benz-recommended engine repair. Even Mercedes-Benz S420 parts will get older and change.

V8/4.2L

Repairs for Your 1999 Mercedes-Benz S420

Nothing stays the same forever. Even your Mercedes-Benz S420's many parts and pieces. When something breaks or fails, we’re ready to help. Select a service or repair below to learn more about what we can do for your 1999 Mercedes-Benz S420.

We Know Mercedes-Benz S420 Engines

Mercedes-Benz S420 drivers trust that their S420 will take them near and far. That might be why you bought it in the first place. Even so, pieces and parts can break down over time. Things can go sideways sometimes. When they do, you might find yourself searching for 1999 Mercedes-Benz S420 engine repair or replacement parts. That’s where Firestone Complete Auto Care comes in. We've serviced millions of vehicles since 1926, and our professional technicians are trained to service Mercedes-Benz S420 engines. If you think something’s wrong with your engine, schedule an appointment at your convenience. Firestone Complete Auto Care is a top choice for professional engine diagnosis, service, and repair at an affordable price.

Illuminated Check Engine Light on 1999 Mercedes-Benz S420

An illuminated check engine light on your Mercedes-Benz S420 is one of the first signs it's time to 'brake' for engine service. A check engine light that’s flashing or steadily illuminated could point to problems with your vehicle's ignition, Potential causes may include a faulty oxygen sensor, bad spark plug, issues with your catalytic converter, or a leaking engine vacuum, to name a few potential sources. Stop by your local Firestone Complete Auto Care to get your S420 issues diagnosed and we’ll figure out why that check engine light is giving you grief. Other signs your Mercedes-Benz S420 engine needs some TLC are oil leaks, or a sinking feeling that something’s wrong.

Mercedes-Benz S420 Engine Repair

If your 1999 Mercedes-Benz S420 needs engine repair, our technicians will make sure you understand what’s going on before they start working on your engine. We make recommendations, but you make the final decision. If a repair isn’t urgent right now, we’ll let you know. If it's necessary for your safety, we'll make sure you understand that, too. We want to give you all the details you need to make an informed decision about your engine repairs. By choosing Firestone Complete Auto Care for S420 engine repairs and you can feel confident knowing that we use Mercedes-Benz-approved parts and components like the timing chain or belt, engine oil seal, ignition coil, or another part.

1999 Mercedes-Benz S420 Engine Q&A

Why does the check engine light come on when I start my S420? Generally, your check engine light turning on upon ignition is not a bad thing. This is just your S420 testing its circuits. The dash light shouldn't stay on. If it does, you might want to bring your vehicle in for service.
Why does my Mercedes-Benz engine sound different? Strange under-the-hood noises can point to problems within your Mercedes-Benz S420 engine. Tapping or knocking could mean you're low on oil. Whistling sounds could mean you have an intake leak or misaligned belt. Squealing can be traced back to a loose fan belt, and grinding might be a sign of brake problems rather than engine issues.
What could damage my Mercedes-Benz S420 engine? Certain driving habits can damage your engine and should be avoided. These habits include 'running on fumes,' flooring the gas pedal while the car is in Park, or accelerating too quickly, too soon. Help sustain your engine’s performance and efficiency by staying miles away from these bad driving practices.
Is it okay to put water in my Mercedes-Benz S420 radiator? Only in emergencies. A 50/50 mix of coolant and water (or a pre-mixed) coolant is recommended. However, if you must keep driving when you're out of coolant, it's better to drive with water in your coolant reservoir than nothing.
What can cause a S420 engine to suddenly stop? Your S420 car engine could stop suddenly due to low fuel, electrical issues, overheating, a faulty ignition system, mechanical troubles, or sensor problems.
Who fixes Mercedes-Benz S420 engines? For Mercedes-Benz S420 engine repair, trust your local Firestone Complete Auto Care. You can make an appointment today at any of our thousands of locations across the U.S.