CHAMPION spark plug (QL77JC4/T10) fires the air-fuel charge with a precisely controlled spark at the correct electrode gap and heat range for your engine's combustion chamber geometry. Plug parameters — Electrode Gap [mm]: 0, Carbon mm, Connector type: SAE, Thread Size: M14x1.25, Spanner Size: 21 mm — determine ignition timing accuracy, electrode longevity, and resistance to pre-ignition deposits across the full RPM range. Replaces OE ignition references: 3579, 4522, 4551, 502180 and 13 more. CHAMPION ignition components are manufactured to SAE and DIN specifications and are approved for use in vehicles covered by manufacturer service agreements throughout Europe. Standard copper-core spark plugs last around 20,000–30,000 miles, while iridium or platinum-tipped plugs can last 60,000–100,000 miles — always follow the interval specified in your vehicle's service schedule. Symptoms of worn spark plugs include rough idling, engine misfires (often felt as a stumble under acceleration), increased fuel consumption, and difficulty starting in cold weather. Spark plug replacement is a straightforward DIY job on most engines — you need a spark plug socket, a torque wrench, and a gap gauge; allow 30–60 minutes for a four-cylinder engine, longer for boxer or V-configurations where access is tighter. Always match the heat range and electrode material specified by your engine manufacturer — fitting a plug with the wrong heat range can cause pre-ignition, fouling, or catalytic converter damage. Replacing spark plugs on schedule maintains optimal combustion efficiency, reduces harmful emissions, and prevents unburnt fuel from damaging the catalytic converter — a component that costs many times more to replace. Every part is dispatched from our UK warehouse with a 30-day money-back guarantee and free hassle-free returns.

Champion, founded in 1907 in Toledo, Ohio, USA, is one of the oldest and most recognised names in spark plug and wiper blade manufacturing. Champion specialises in spark plugs, glow plugs, wiper blades, and ignition components for passenger and commercial vehicles. As a historic OE supplier and the spark plug of choice in numerous motorsport championships, Champion products deliver proven ignition performance. With over a century of innovation and billions of spark plugs manufactured, Champion is a trusted brand for reliable engine starting and efficient combustion.