Skip the auto shop - Our mechanics make house calls

Q: Car misfires and fumbles during acceleration but regains pace. - 2003 Mercedes Benz C230

asked by on

My car seems to misfire and has trouble engaging when going uphill or accelerating when entering freeways. Last night it stalled on me for approximately 30 seconds but returned to normal afterwards. I'm not sure if I'm having issues with my spark plugs, fuel filter, or fuel pump. Any advice or insight you could offer would be greatly appreciated.

My car has 163000 miles.
My car has an automatic transmission.

Hi! The symptoms you describe sound like a misfire caused by ignition components. Running ok until a heavy load is put on the engine, then stumbling and misfiring is typical of an ignition-related misfire. Spark plugs, wires, or coils are the usual suspects, and would be accompanied by a Check Engine Light and misfire codes. A fuel pressure test would provide helpful diagnostic information to confirm adequate fuel supply. An experienced technician, like one from YourMechanic, using a scan tool would be able to look at data that provides clues on which way to proceed. From there, they will be able to diagnose the misfire condition and conduct proper repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Car misfires and fumbles during acceleration but regains pace. - 2003 Mercedes Benz C230

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car hesitated and transmission engaged before acceleration

Some of the CX5s have been having severe transmission problems, which is exactly what it sounds like your's is experiencing. There have been a couple cases of complete failure, even with under 1000 miles on them. It's possible that it...

Q: Engine flooding with fuel

Hi there. From the description you have provided, your vehicle's exhaust leak on the driver's side has caused several issues for you. Assuming you have followed procedure in replacing your engine's head gaskets and all is correctly reassembled, it could...

Q: The truck is shaking at takeoff and stops

Shaking or vibrating may be caused by many different things such as faulty spark plugs, poor fuel pressure or misfires. Other things such as a faulty idle air control valve may cause the engine idle to drop below the normal...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...