Signs and Symptoms of Spark Plug Failure

Spark plugs are the most important part of a car to start up the engine. They conduct high tension electricity and ignite air/fuel (A/F) mixture to start the vehicle. Good spark plugs enable smooth vehicle movement, increase fuel efficiency, and reduce discharge of polluting gases.

If these plugs are unclean or damaged, it affects the performance of your car badly. This article discusses briefly the symptoms that you find in your car because of bad spark plugs, and different signs on these plugs to identify the bad ones.

Symptoms

Difficulty in starting: Starting problem is the most common symptom.

Engine misfire: Engine misfire makes your vehicle stammer, and emit more polluting gases. This is due to bad functioning or failure of spark plugs in at least one cylinder of the engine. The cylinder fails whenever the air/fuel mixture in its combustion chamber is not ignited.

Rough engine idle: Rough engine idle means heavy vibration occurring all through the vehicle while running. This is again due to bad spark plugs, and could lead to severe damage to the engine if ignored.

Poor acceleration: Poor acceleration is also one of the most common symptoms that can be observed. Acceleration of the vehicle goes down, and it will not pick up speed if the spark plugs of the vehicle are damaged.

Vehicle jerks: When the spark plugs malfunction, more air is sucked by the engine affecting A/F ratio, and this causes jerks while the vehicle is running. The engine starts and stops all of a sudden.

Less mileage: Bad spark plugs affect the fuel efficiency of the engine. As they become worse, the mileage of the vehicle reduces drastically.

Poor engine performance: These symptoms such as less fuel efficiency, vibrations, jerks, etc. indicate bad performance of the engine due to bad spark plugs.

Signs

Oily deposits: Deposit of oil occurs when the valves of a cylinder or piston rings are worn or split, and excess oil enters the chamber. This is indicated by grease or oil on it.

Carbon deposit on the plug: The carbon deposit is because of weak ignition voltage system or the carburetor of the vehicle taking in more air. This can be identified by soft black or gray deposits.

Ash deposits on its insulator: This occurs due to accumulation of combustion deposits on the plug. Ash is non-conducting, covers the nose of the spark plugs, and then blocks them from producing spark. Ash deposits can be clearly seen on the plug.

Chipped insulator: This may be because of pre-ignition shock causing physical damage to the plugs or because of mechanical damage by foreign elements when its transition between the electrodes happens. The damage is clearly visible when observed.

Therefore, it is sensible to check the condition of the spark plugs of your car when you see any of these signs and symptoms. Regular cleaning and replacing them whenever required gives your vehicle a long life and better engine performance.

Auto Novice

Auto Novices is a blog, that was set up in November 2011, which tries to help inform new & old automobile owners about various subjects from keeping their car in good working order right through to tips on buying a new & used motorbikes. GUEST POSTS: If you would like to produce a guest post for this blog then please contact us via the link in the navigation menu at the top of the page.