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. …show more content…
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