Diagnosing Spark Plug Problems

When we are talking about automotive electrical system, how can we miss on the spark plugs. Spark Plugs, as the Wikipedia defines, are electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed aerosol gasoline by means of an electric spark. Often, a little problem with the spark plug is the reason behind the breakdown of the vehicle in the middle of road.

A little maintenance and few D-I-Y tips will help you keep these auto parts in place. But before that for repair, you need to know the common problems behind spark plugs. Lets together find out the common spark plug problems.

Problems With Your Spark Plug

• There are times, when your car's engine cranks, isn't it? But then, nothing happen after, i.e. It doesn't start after that. This is possible because of the spark plug.


• In some cases, the engine might run. After that, it often misfires. Check for any worn out spark plug. In such a case, it is possible that these auto parts have either fouled or probably the reason is bad spark plug wires.


• High or Low Voltage also indicate problem. On an oscilloscope, if you observe the firing pattern of each cylinder, you might be able to diagnose the problems yourself. If the firing voltage is noticed to be normal, it means there is excessive resistance in a plug wire. Other possibilities can be loose plug wire, badly worn or too wide spark plug.


• In case you notice that there is a lower voltage in firing pattern, then it indicates, a damaged or shortened plug wire.


• Fouling is something that should be avoided. One important cause of it is deposits of oil or fuel upon the plug electrodes.

Reasons Why You Need To Change the Spark Plugs

There are a number of factors that can be the cause for replacement of spark plugs. Some of them are:

Fouling – Incase you notice that there is a single fouled spark plug, you need to be cautious and get it replaced soon. Otherwise, you might have to suffer the loss of 25% of output of four cylinder engines.

For Preventive Maintenance – This is always suggested as to avoid any major auto repair.

Due to Worn Out Electrodes – That increases the distance between the electrodes and finally increases the firing voltage.