Skip the auto shop - Our mechanics make house calls

Q: My engine light is on, why does my car hesitate sometimes when trying to accelerate or after I brake?

asked by on

My engine light came on a year ago after starting up my car on a normal day. Upon the light turning on my car began to shake like it's about to go out when I started it but did not. It kept shaking a few more times as I continued to drive it to possibly "warm it up" to get it driving, which after a few minutes of accelerating and trying to drive it, the car drove normally. Months later now, when accelerating the car does this hesitation action as if it's not making the right connections, then it goes after a few seconds. It does this now a few times a day the allows me to drive normally. I took it to autozone to have it ran by a computer and it diagnosed some possible misfires, spark plugs or injector fluid issues. Could it be my catalytic converter or my oxygen sensor?

My car has 160000 miles.
My car has an automatic transmission.

Misfires can be caused by a number of things. Poor fuel quality can cause misfires across all cylinders and possibly clog fuel injectors. Also, worn spark plugs can cause misfires as can the ignition coils that supply the spark plugs with the electricity to fire properly. Any of these will cause loss of power and economy. The oxygen sensor can also be a cause of poor performance but usually will set a fault code if the sensor has gone bad. Typically, a bad catalytic converter is not the "cause" of performance issues but is usually the "effect" of misfires and poor engine performance. If the catalytic converter is bad, something else (like misfires) made it go bad. Replacing the converter without addressing what made it go bad is not the route to take.

Since the cost of randomly replacing components can run into the hundreds, if not thousands of dollars, have a certified technician look into why the check engine light is on to isolate the exact cause. It will save you time and money.

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!
  • Home
  • Questions
  • My engine light is on, why does my car hesitate sometimes when trying to accelerate or after I brake?

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: oil change

Hi Shamoy. Thanks for contacting us today. It really depends on which engine and fuel type you have for your VW Jetta. You can find the recommended engine oil, including the right viscosity, grade and how much to add in...

Q: Shaking on acceleration over 3,000 rpm.

Check the engine for a misfire. Check the spark plugs and see if they are working and if there is park to the spark plugs. If the spark plugs are clean and there is spark to the spark plugs, then...

Q: rpm

The tach needle was put back on wrong when you installed it. The tach needle shaft must have moved once you pulled the needle off. The shaft can be moved very easily by just tapping on the gauge. What you...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.