Peugeot 308 EP6

The Peugeot 308 EP6 has a reliability score of 42/100, rated "RISKY". Clever engine, notorious for costly failures

The most frequently reported issues are Timing Chain Stretch and Failure, Excessive Oil Consumption, Carbon Buildup on Intake Valves and Ports, Variable Valve Timing (VVT) Solenoid and Cam Phaser Faults, among others. See the Known Issues section above for symptoms, affected mileage, and repair costs.

Yes, this is a documented issue on the EP6, typically appearing around 60,000-150,000 km. The EP6 THP engine suffers from well-documented timing chain stretch, particularly the secondary chain. A stretched or failed chain can cause catastrophic engine damage. Multiple forum threads confirm this is a known issue on the THP 150-208hp Prince engine, with owners actively replacing chains and tensioners as preventive maintenance rather than waiting for failure. Typical repair cost: €800-2,500. DIY difficulty: Expert.

Yes, this is a documented issue on the EP6, typically appearing around 50,000-120,000 km. Forum data confirms severe oil consumption on EP6 engines, with some owners reporting several hundred ml lost per few hundred km. This is linked to valve stem seal wear, piston ring wear, and cam phaser seal degradation. Left unchecked, low oil level accelerates timing chain wear and can damage the catalytic converter. Typical repair cost: €200-1,500. DIY difficulty: Moderate.

Yes, this is a documented issue on the EP6, typically appearing around 60,000-120,000 km. As a direct injection engine, the EP6 does not wash intake valves with fuel, so carbon deposits build up on valve backs and intake ports over time. Owners describe intake ports caked in carbon with chunks breaking off, causing sluggish performance and misfires. Oil catch cans are widely recommended by the community as a preventive measure to slow buildup. Typical repair cost: €300-900. DIY difficulty: Moderate.

Yes, this is a documented issue on the EP6, typically appearing around 80,000-160,000 km. The EP6's continuously variable valve timing system uses cam phasers on the intake camshaft, and is prone to oil control solenoid clogging and phaser seal wear. Because the Prince engine family was jointly developed with BMW, owners sometimes refer to this fault using the borrowed term 'VANOS', though Peugeot documentation calls it VVT. Fault codes P1336 and P1339 (camshaft position/correlation) are repeatedly reported on 308 1.6 THP engines and often coincide with rough idle and hesitation. Typical repair cost: €400-1,200. DIY difficulty: Moderate.

Yes, this is a documented issue on the EP6, typically appearing around 100,000-180,000 km. Head gasket replacement is reported on EP6 THP variants at higher mileage. The all-aluminium construction is sensitive to overheating, and ongoing oil consumption can compound thermal stress on the head gasket over time. Typical repair cost: €600-2,000. DIY difficulty: Expert.

Yes, this is a documented issue on the EP6, typically appearing around 100,000-200,000 km. Owners report camshaft wear and, in some cases, incorrect valve timing developing on high-mileage EP6 units. Combined with oil consumption and VVT issues, the valve train is a wear-sensitive area that benefits from regular inspection. Typical repair cost: €500-1,800. DIY difficulty: Expert.

The EP6 THP is a technically impressive engine let down by serious real-world reliability issues that are well-documented across owner communities. Timing chain failure, oil consumption, and carbon buildup are not rare edge cases, they are expected maintenance items on this engine regardless of power output. Only buy a used 308 with EP6 if you can verify full service history with short oil change intervals, confirmed timing chain replacement, and no active fault codes. Budget €1,500-3,000 on top of purchase price for preventive work if chain history is unknown, and fit an oil catch can immediately after purchase.

Do not pick a used 308 THP based on the hp figure on the registration document alone. All power outputs share the same rear timing chain design, the same direct injection carbon buildup tendency, and similar oil consumption risk. The 163hp and 208hp tunes use somewhat stronger internals to handle their higher outputs, but this does not meaningfully reduce chain or carbon problems since those are shared architecture issues, not tune-specific ones. Prioritise documented chain replacement and short oil change intervals over chasing the higher-hp variant.

Before buying, check: Cold-start the engine and listen for timing chain rattle lasting more than 2-3 seconds; Check oil level and condition, look for rapid consumption signs or milky emulsification; Scan for fault codes especially P1336 and P1339 related to cam timing/VVT; Request full service history and confirm oil changes every 10,000 km or less with correct spec oil; Ask specifically if the timing chain kit has been replaced and inspect for any recent chain-related work.

There's no fixed mileage limit, it depends on maintenance. The parts worth budgeting for proactively are: Timing Chain Kit (chain, tensioner, guides) (80,000 km), VVT Cam Phaser Oil Control Solenoid (80,000 km), Intake Valve Carbon Cleaning (60,000 km), Oil Catch Can (0 km). Engines that clear these checkpoints with documented maintenance commonly continue well beyond typical ownership periods.

Estimated ownership cost is €1,500-4,000 over 3 years, covering preventive timing chain replacement, VVT solenoid/seal work, carbon cleaning, and higher than normal oil top-ups typical for this engine, based on known issues and typical service needs.

Owners report real-world fuel consumption of around 7.3 L/100km.

Community-reported real-world usage suggests changing oil every 10,000 km using 5W-30 fully synthetic, ACEA A5/B5 specification (PSA-approved oils such as Total Quartz 9000 5W-30 or equivalent), often more conservative than the official service schedule.

The EP6 is also found in: BMW Mini Cooper S R56, Citroën DS3 THP, Citroën C4 THP, Peugeot 207 THP, Peugeot RCZ THP, Peugeot 3008 THP, MINI One/Cooper R55/R56/R57.

Clever engine, notorious for costly failures The biggest recurring complaint is Timing Chain Stretch and Failure. Largely negative among long-term owners. The EP6 THP is respected for its performance but widely criticised for timing chain stretch, oil burning, and expensive repair bills. Community consensus is to avoid high-mileage examples without documented chain replacement and to use short oil change intervals from day one.