Q: Car shakes when accelerating and has a hard time starting

asked by on

Just got a bunch of work done on car- oil change, break pads, alignment and ear shocks. Mechanic said we might wanna get new rear tires soon but not needed yet and we just got 2 front tires a month ago. It was shaking when accelerating between 30-40 mph when we brought it in and now it shakes almost every acceleration and has a hard time starting on and off. What can it be?

My car has 96000 miles.
My car has an automatic transmission.

Shaking or vibration 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 idling RPM which may also cause the motor to shake or vibrate more than normal. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Anytime a misfire is caused, this causes an imbalance in the motor which will cause the motor to shake or vibrate. Other issues that may cause this type of shaking or vibration might be broken engine mounts or potentially tires that are out of balance or worn improperly. Engine mounts are generally rubber mounted braces that hold the engine in place to the chassis of the car. When these break or become weak or faulty, this may cause the engine to vibrate heavily. When tires are out of balance, as the speed of the vehicle increases, the vibration will become much more noticeable and pronounced. I would suggest having an expert from YourMechanic come to your location to diagnose and inspect your vehicle using a scanning tool which will more accurately indicate what specifically may be causing this.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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
  1. Home
  2. Questions
  3. Car shakes when accelerating and has a hard time starting

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: Q: How do I install the spare tire?

Drive your car long enough and you’ll experience it – having a flat tire. It’s no fun at all, but the spare tire will let you get back on the road (and to get your flat repaired or replaced). Of...

Q: Q: The car has trouble starting after gas tank is filled up

Hi There, It sounds like you may have a problem with your evaporative emissions control system. Your car has a small purge valve called a purge solenoid in the Evaporative Emissions system that controls the venting of fumes from the...

Q: I need the front timing cover gasket replaced on my 2012 GMC Acadia to stop an oil leak. How much for the parts and labor?

If you are referring to the crankshaft seal on the timing cover, please use YourMechanic's front crankshaft seal replacement service page to obtain an instant quote. If you are referring to the timing cover to engine (front engine cover) gasket,...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...