Skip the auto shop - Our mechanics make house calls

Q: Cylinder 3 is misfiring

asked by on

I am getting a Check Engine code P0303, which is a misfire on cylinder 3. I am not exactly sure whether the cylinder needs cleaning or replacing, or if it is just a spark plug.

A: Misfire on cylinder 3 usually mean you have...

Misfire on cylinder 3 usually mean you have a bad spark plug or spark plug wire. If you haven’t had a tune up in a while I would recommend having a technician, such as one from YourMechanic, come out and replace your spark plugs, wires, and air filter and see if that helps. I would also have them replace the fuel filter as well since a misfire may be caused by the fuel system as well.

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!

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: The car makes a weird sound, especially when going up hill or when accelerating, should I be concerned?

There are a few different types of noises the engine can make depending on the problems it might have. A light rattle noise that only happens during acceleration can be a lean spark knock or ignition problems. Your description makes...

Q: Won't crank?

Hi there. From the description you have provided, there may be a poor connection at the battery terminals. The replacement battery may have already failed. The alternator may not be properly charging the battery. The starter may be drawing too...

Q: How much does it cost to change and or fix the coolant thermostat

Hi there. Quotes cannot be generated via the ask a mechanic portal. Your request is being forwarded to customer service. Please have your vehicle make, model, year, mileage, and VIN readily available. Your Mechanic has several available technicians that can...

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...
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...
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.