
Audi does not require spark plug replacement at 20,000 kilometers. The replacement interval for Audi Q5 spark plugs: Under normal maintenance conditions, replacement is recommended at 40,000 to 60,000 kilometers. However, this may vary depending on the brand and engine type. It is advisable to follow the owner's manual. You can refer to the following maintenance standards: Platinum spark plugs should be replaced at 40,000 km, ordinary nickel alloy spark plugs at 20,000 km, and iridium spark plugs at 60,000-80,000 km. How spark plugs work: The spark plug's ground electrode is connected to the metal shell, which is threaded into the engine block via the cylinder head. The insulator primarily serves to isolate the metal shell from the center electrode. The terminal nut is the part that contacts the high-voltage coil. When current passes through the terminal nut and center electrode, it ionizes the medium between the center electrode and ground electrode to generate a spark, thereby igniting the air-fuel mixture in the cylinder.

Last time I took my Audi for maintenance, the technician reminded me that the spark plugs need to be replaced at 20,000 kilometers. Audi's turbocharged engines operate under high pressure and have demanding ignition requirements. Worn spark plugs may have increased gaps, affecting ignition efficiency. After the replacement, I noticed the throttle response became quicker, and fuel consumption stabilized. Although it's a bit expensive, I figured the manufacturer designed it this way for a reason—it's not worth risking damage to the ignition coils just to save a little money, as repairs would be even more painful. If you experience sluggish acceleration or difficulty starting the engine when cold, it’s likely time to change the spark plugs.

The Audi manual clearly states that spark plugs should be replaced every 20,000 kilometers, especially for those turbocharged (T) engines. I learned this the hard way with my A4—I delayed replacement until 30,000 km, and the cold starts shook like crazy, plus one ignition coil burned out, costing me thousands in repairs. When I finally removed the old spark plugs, the electrodes were visibly deformed from overheating. Replacing them earlier would've prevented this entirely. Now I strictly follow the manual—ignore those who claim you can wait until 50,000-60,000 km. The manufacturer's engineers know these cars best. That said, if you mostly drive short urban trips at low speeds, spark plug wear will be significantly reduced.

My experience is to focus on the actual condition of the car rather than obsessing over the mileage. When I took my Q5 in for its 20,000 km service, the mechanic checked the spark plugs with a borescope and said they were still in good condition, advising me to drive another 5,000 km. However, if symptoms like sluggish acceleration, rough idling, or a sudden increase in fuel consumption appear, you should get it checked immediately, even if it hasn’t reached 20,000 km. Audi engines are delicate—a faulty spark plug could damage the ignition coil, and the repair cost would be enough to replace ten sets of spark plugs. Owners who frequently drive on highways should follow the manufacturer’s recommended replacement intervals, while those who mainly use the car for city commuting can extend the interval slightly, provided they regularly check the data with a diagnostic scanner.


