Diesel injector failure is expensive — a single unit runs £200–500 fitted, and a full set on a 6-cylinder can top £2,000. This guide covers real costs, symptoms and whether cleaning is a genuine alternative.
This Repair Cost Guide guide combines structured analysis — verdicts, risk scoring and cost ranges where we have enough data — with real fault cases pulled directly from MyCarFault's reporting database, so the guidance below reflects what owners actually experience rather than manufacturer specifications alone. Background and analysis come first, followed by the linked fault reports and related guides you can jump to directly using the links above.
Common rail diesel injectors are precision components operating at pressures of 1,800–2,500 bar, cycling thousands of times per minute. Modern piezoelectric injectors are even more precise than the solenoid units they replaced. When they fail — through wear, contamination or electrical failure — the symptoms range from rough idle and misfires to complete non-start. Replacement is expensive, but running failed injectors causes secondary damage to the catalytic converter and turbocharger.
Short distances only. Misfires stress the catalytic converter and turbo. A leaking injector seal (diesel smell in cabin) should be treated urgently — diesel in the engine oil causes rapid bearing wear.
From reputable remanufacturers, yes. Look for suppliers with flow-tested and coded units and a minimum 12-month warranty.
There is no fixed interval. Good fuel quality, regular oil changes and not running the tank very low extend injector life. Many last 150,000+ miles with no issues.