Why does the check engine light come on when I start my 420SEL?

It’s usually normal for your check engine light to turn on upon ignition. This is just your 420SEL 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 420SEL engine. Knocking or tapping could be a symptom of low oil. Whistling could mean a belt is misaligned or there's an intake leak. Squealing may be caused by a loose fan belt, and grinding could be a sign that something is wrong with your brakes — not the engine.

What could damage my Mercedes-Benz 420SEL engine?

Certain driving habits can damage your engine and should be avoided. These habits include 'running on fumes,' revving your engine while the vehicle is in Park, or pushing 'the pedal to the metal' before the engine has warmed up. Steer clear of these habits to help protect engine performance and efficiency.

Can I put water in my Mercedes-Benz 420SEL radiator?

While it’s not recommended, you can use water in your 420SEL radiator in emergencies. Normally, you should only use a 50/50 mix of coolant and water or a pre-mixed coolant. However, if you are completely out of coolant and must continue driving, it’s better to have water in your coolant reservoir than nothing.

What can cause the engine in my 420SEL to suddenly stop?

If your 420SEL car engine suddenly stops, it could be due to overheating, low fuel, a faulty ignition system, sensor problems, electrical system trouble, or mechanical issues.

Who fixes Mercedes-Benz 420SEL engines?

Your local Firestone Complete Auto Care offers Mercedes-Benz 420SEL engine repair. Schedule an appointment today at one of our thousands of locations nationwide!

Reliable Repairs for 1991 Mercedes-Benz 420SEL Engines

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1991 Mercedes-Benz 420SEL Trim Options

Select your Mercedes-Benz 420SEL trim level to learn more about Mercedes-Benz-recommended engine repair. Use the following chart to find information.

V8/4.2L

Mercedes-Benz 420SEL Repairs and Services

Nothing lasts forever. Even your Mercedes-Benz 420SEL's many parts and pieces. When something breaks, we're ready. Select a repair or category to learn more about 1991 Mercedes-Benz 420SEL services.

We Care for Mercedes-Benz 420SEL Engines

Mercedes-Benz 420SEL engines are known for their reliability. You probably thought about that when you got it. Even so, pieces and parts can break down over time. Sometimes plans go sideways. If the unexpected strikes, you may search the internet frantically for quick and affordable 1991 Mercedes-Benz 420SEL engine repairs. That's when it's time to head to Firestone Complete Auto Care. We've serviced more than 500 million vehicles since 1926, and our technicians know Mercedes-Benz 420SEL engines. Schedule a courtesy inspection at the first sign of engine trouble. Firestone Complete Auto Care offers both trustworthy and affordable engine repairs.

Illuminated Check Engine Light on 1991 Mercedes-Benz 420SEL

An illuminated check engine light on your Mercedes-Benz 420SEL is one of the first signs it's time to 'brake' for engine service. A check engine light that’s on or flashing could be a symptom of a serious problem in your car’s starter, Possible causes can include a failing oxygen sensor, worn spark plug, a clogged catalytic converter, or an engine vacuum leak, to name a few possible causes. Bring your 420SEL in for an on-board diagnostic check and we’ll figure out why that check engine light is giving you grief. Other signs your Mercedes-Benz 420SEL engine needs some TLC are oil leaks, or misfiring.

Engine Repairs for Your 1991 420SEL

If your 1991 Mercedes-Benz 420SEL needs engine repair, our technicians will make sure you understand what’s going on before they start working on your engine. We never do any work without your sign-off. If a service can wait, we’ll make sure you know. We'll also tell you if it's necessary for your safety. We seek to give you all the info you need to make a smart decision about our services. By choosing Firestone Complete Auto Care for 420SEL engine repairs and you can feel good knowing that we only use Mercedes-Benz-compliant replacement parts such as the serpentine belt, motor oil seal, ignition coil, or other parts.

1991 Mercedes-Benz 420SEL Engine Q&A

Why does the check engine light come on when I start my 420SEL? It’s usually normal for your check engine light to turn on upon ignition. This is just your 420SEL 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 420SEL engine. Knocking or tapping could be a symptom of low oil. Whistling could mean a belt is misaligned or there's an intake leak. Squealing may be caused by a loose fan belt, and grinding could be a sign that something is wrong with your brakes — not the engine.
What could damage my Mercedes-Benz 420SEL engine? Certain driving habits can damage your engine and should be avoided. These habits include 'running on fumes,' revving your engine while the vehicle is in Park, or pushing 'the pedal to the metal' before the engine has warmed up. Steer clear of these habits to help protect engine performance and efficiency.
Can I put water in my Mercedes-Benz 420SEL radiator? While it’s not recommended, you can use water in your 420SEL radiator in emergencies. Normally, you should only use a 50/50 mix of coolant and water or a pre-mixed coolant. However, if you are completely out of coolant and must continue driving, it’s better to have water in your coolant reservoir than nothing.
What can cause the engine in my 420SEL to suddenly stop? If your 420SEL car engine suddenly stops, it could be due to overheating, low fuel, a faulty ignition system, sensor problems, electrical system trouble, or mechanical issues.
Who fixes Mercedes-Benz 420SEL engines? Your local Firestone Complete Auto Care offers Mercedes-Benz 420SEL engine repair. Schedule an appointment today at one of our thousands of locations nationwide!