There are a variety of problems that crop up when spark plugs need to be replaced. Some of the symptoms include difficulty starting, lack of acceleration, rough idle and increased fuel consumption. In general, spark plugs that need to be replaced cause a variety of poor performance symptoms in a car. Many of these symptoms have other causes, but together they can indicate bad spark plugs.
Spark plugs can be a reason for a car not starting, as lack of spark is one of the two reasons for a car not to start. It can also be the reason behind unusual battery drain. Misfiring cylinders are another symptom of faulty spark plugs. A misfire causes the car to jerk briefly and then continue its normal operation. Similarly, this symptom could be due to the engine surging, which is another sign of faulty spark plugs.
If a car suddenly seems to be consuming way more fuel than usual, the spark plugs could be the culprit. This is due to incomplete combustion because of the inadequate spark. Fuel consumption can go up by as much as 30 percent in these cases. Similarly, the vehicle might feel sluggish and hesitate or lurch upon acceleration.Learn More
Oil on spark plugs, also called oil fouling, is commonly caused by failing valve stem guides and bad stem seals. As pressure builds up in the crankcase, excessive oil enters the combustion chamber through worn-out piston rings or cylinder walls and forces its way to spark plugs. Oil fouling can also be caused by transmission fluid sucked through malfunctioning vacuum modulators or leaking lubricants from engine turbochargers.Full Answer >
To clean spark plugs, disconnect the cables, remove the spark plugs, scrub them with sandpaper and a wire brush, wipe them with solvent, reinsert them, and reattach the cables. This 45-minute process requires work gloves, a bench vise, sandpaper, a brush, a ratchet wrench, solvent and rags.Full Answer >
Spark plugs are replaced every 80,000 miles. Many vehicle manufactures claim their spark plugs can last up to 100,000 miles, but as the gap in the plugs widen, the chance of vehicle problems rises significantly. Some of these problems include bad gas mileage and reduced engine performance.Full Answer >
Some of the reasons that a car can stall when accelerating are a defective throttle position sensor, low fuel pressure and spark plugs that need to be replaced. When the "Check engine" light is on, a code scanner can be used to identify the cause more accurately.Full Answer >