Skip the auto shop - Our mechanics make house calls

Q: Misfire in cylinder 2 and 6

asked by on

When I first cold start it every morning it runs perfectly no problems. A good 20 minutes pass and it starts misfiring and the whole car shakes. It shakes at a point where the steering wheel shakes also. I also hear a tapping sound when I first start it up but goes away and very faint after a 5 minute drive. If it helps I get 13.8mpg now.. a week ago I got 17mpg. Is it the spark plugs or something more major?

My car has 294500 miles.
My car has an automatic transmission.

A: It is possible that you have an ignition co...

It is possible that you have an ignition coil going bad. Once heat builds up, resistance in the ignition coils increase. If you have a weak coil, it will sometimes cause a misfire when it is hot.

The misfires are why your fuel milage is worse. With two cylinders not making power, it may take more fuel to produce the required power. The tapping sound may be caused by incorrect valve adjustment or other valve train related components. A certified technician, like one from YourMechanic, will be able to diagnose the cause of the misfiring issue and assist you with repair.

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: Ignition problem and car won't start - 2002 Jeep Grand Cherokee

Hi there. I would need to know if, when it will not start, the engine cranks over or you get nothing. If it will not even crank over, then most of the time this is caused by a failing starter....

Q: Check Engine Light with codes P219B and P0305

Hi there. The first code denotes an air fuel mixture ratio concern; and the second code, P0305, is a misfire detected on cylinder 5. There are several possible causes and both codes could be a related fault. An ignition coil,...

Q: Jeep won't turn over after sitting for 8 hours 2001 Jeep Cherokee

Hello - I would first check the battery cables and ground straps for corrosion, or other poor-connectivity problems. A strong battery can be hampered by poor connections, which will sometimes finally pass current. A failing starter solenoid (burned contacts) will...

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 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.
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.