Skip the auto shop - Our mechanics make house calls

Q: Random misfiring. Check engine light is on. Running real rough. Bad PCM?

asked by on

The check engine light is either on or blinking the engine is running real rough different lights on the dash go on and off and very loud when driving. Wants to stall at idle, shakes badly. Changed out the spark plugs and had absolutely no effect.

My car has 156000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. There are severa...

Hi, thanks for writing in. There are several malfunctions that can cause a rough running condition. The spark plugs could be an issue, but it could also be a problem with the ignition, a fuel supply problem, or even a wiring issue. It would be best to have a certified mechanic, like those available at YourMechanic.com, to perform some diagnostics on the vehicle to identify exactly what is causing the rough running condition.

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・Save up to 30%

Get a quote

What others are asking

Q: Engine races or revs while driving.

Hi There, This may be a sign of low transmission fluid or a faulty transmission control solenoid. As you’re going down the road, the car’s computer analyzes data being sent by vehicle speed sensors and engine speed sensors. Based on...

Q: How do I turn off the sound horn feature?

The sound horn is a locking feature. When you lock your car with the remote keyless entry (RKE) transmitter, your horn beeps as confirmation that your vehicle is locked. If you find the sound horn annoying or disruptive, you can...

Q: Whirring sound coming from engine

Hi there. That is a classic sound of a bad Power steering pump or it may be low on fluid. Over time, the high pressure power steering hoses tend to start leaking and cause the pump to run dry and...

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...
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...