Skip the auto shop - Our mechanics make house calls

Q: The car accelerates slowly, hesitates and shudders

asked by on

My car started having some issue the other day, while I was driving and tried to accelerate very quickly. The car seemed to lose power and there was a delay in picking up speed. The engine hesitated and if I attempted to accelerate more, it would shudder. The problem is the same if the car idles at the red stop and I try to accelerate. I fear that it would stall, so in those situations I put it in park just in case. Occasionally, the engine seems to gather the speed quickly and but the car wouldn't run fine afterward. It would then hesitate and shudder yet again. The check engine light is on as well. The car shakes only when it is put in drive, not while I accelerate from neutral. I had the spark plugs replaced. What is causing these issues? Is it a serious engine problem?

A: Unmetered air can cause this type of hesita...

Unmetered air can cause this type of hesitation and shuddering. Too much air compared to fuel will cause a lean misfiring condition. Fault codes need to be read out of your Mercedes C320’s engine computer to see if there are any underlying issues and those issues are corrected.

The induction should be inspected and checked for vacuum leaks. Also, fuel pressure and volume should be checked as well if the induction system checks out okay. A partially clogged fuel filter can cause a starvation issue on heavy acceleration. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the tools and expertise to conduct this type of diagnosis and repair for your acceleration issue.

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

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: Hesitation before engine starts up.

Hello, do you mean a lag "while" the starter turns the motor over, before it actually starts? Or a lag between turning the key to '"start" and when the starter kicks off? A lag while the starter is turning, but...

Q: Truck accelerating slowly.

Hey there. This may be a sign of a faulty transmission control solenoid. Modern automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car's computer activates a transmission solenoid, which directs transmission...

Q: 05 Monty Carlo problem is hesitate and surgery between 45 to55mph. It is the throttle body sensor. It has 14400.00 miles replace

There are quite a few possibilities that a mechanic would consider in diagnosing an engine hesitation issue. The most efficient thing is do is schedule a hesitation diagnostic and the responding certified mechanic will simply go through a diagnostic "decision...

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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.