Q: What is causing the engine misfires?

asked by on

I had a P0301 code so I changed all spark plugs and the coil for cylinder 1. Then, I cleared the code. Soon after a P0303 code popped up. I've been having low RPM at stops, poor gas mileage and a lot of smoke out of the muffler when I start the vehicle in the morning. What could be the cause? Camshaft sensor? Leak?

My car has 143560 miles.
My car has an automatic transmission.

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. What is causing the engine misfires?

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: jeep over heating

This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning...

Q: I'm having a problem with arcing from the plug wires.

The problem you are having is not due to the ignition system but is a result from an improper amount of fuel getting into the cylinders. If your engine is running lean, then it may cause the engine to not...

Q: My radiator went out but I have to pump on gas for it to start

Pumping on the gas does not do anything with a fuel injected car. Try just holding gas pedal at 1/4 throttle and see if it starts better? As far as the hard start if coolant went all over engine you...

Related articles

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 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...
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.