Q: Engine misfires and check engine light is always on

asked by on October 29, 2015

The check engine light has lit up fairly often in my 2009 Honda Accord, and the issue usually involves something like the gas cap being loose. The other day the check engine light began flashing on my way home from work. I tried to make it home but had to pull over when the engine started sputtering and running rough. I think the engine is misfiring, which is a huge problem for a car still under 60,000 miles. What could be the real problem, and how should I proceed to get my car back on the road soon?

It’s always a good idea to pull over and turn off your vehicle when the check engine light is blinking. A blinking check engine light usually means there is a severe misfire in one or more of the cylinders. Most of the time, a misfire symptom is the result of a fouled spark plug. Honda now recommends changing spark plugs at 110,000 miles, however it is a known fact that spark plugs are considered a wear item and they do indeed wear out. There are a lot of factors that go into a spark plug wearing out or prematurely wearing out. One thing to consider is the type of gasoline being used in the vehicle. A top tier gas is recommended in most newer vehicles. This is because top tier gas contains additives which keep the engine free of deposits that may cause spark plugs to foul prematurely.

Honda is aware of this concern and has issued a technical service bulletin to help reduce and, in some cases, eliminate this concern. This technical service bulletin advises the technician to update the vehicle’s engine computer. This update improves fuel injector and variable camshaft timing during cold starts and eliminates excessive fuel from fouling out the spark plugs. I recommend you have a certified mechanic inspect your ignition system to determine the exact cause of this misfire so the proper repairs and preventative maintenance can be performed and get you back on the road again.

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