Peugeot 508 W2

The most common PSA diesel (1.6L HDi, 68-85 kW), evolving through many stages from Euro 4 to Euro 6. THE defining problem is the turbocharger: the oil feed line clogs with soot particles and kills the TD025/GT1544V turbo — sometimes as early as 50,000 km. Injector seals, EGR carbon buildup, and DPF issues on short trips are additional trouble spots. With regular oil changes and highway driving, it remains a frugal, long-lasting engine.

• !! Turbocharger total failure from oil sludge from 100,000 km

  The 1.6 HDi is notorious for repeated turbocharger failures. Soot particles in the oil alter viscosity, oil lines coke up and the turbocharger runs dry. A second failure after replacement without addressing the root cause is common.

  Symptoms: Whistling from the turbocharger, severe power loss, blue or black exhaust smoke, oil leaking from turbo, engine enters limp mode
  700–2,500 $
  Ad turbocharger 1.6 HDi 9HZGarrett GT1544V0375J6Turbo Ölzuleitung DV6
• !! Leaking injectors with diesel in the engine oil from 120,000 km

  The copper sealing rings on the injectors wear out, allowing combustion gases and diesel to enter the cylinder head. Oil dilution by diesel can lead to engine damage. Affects all 1.6 HDi variants.

  Symptoms: Diesel smell at the dipstick, rising oil level, black deposits around injectors, rough engine running, hissing noises at the cylinder head with engine running
  300–800 $
  Ad fuel injector Kupferdichtring 1.6 HDifuel injectorgasket DV6fuel injector Hülse 1.6 HDi
• !! Premature camshaft and chain wear from 130,000 km

  The cam-to-cam timing chain between inlet and exhaust camshafts can stretch or snap. Hydraulic chain tensioners fail, causing valve timing shift and in extreme cases engine damage.

  Symptoms: Rattling on cold start, rough engine running, engine management light, power loss, in extreme cases sudden engine shutdown from chain snap
  800–2,500 $
  Ad timing chain DV6camshaft 1.6 HDichain tensioner 9HZ

+ 5 more engine weaknesses + vehicle weaknesses

Powerful PSA diesel (2.0L HDi, 100-133 kW) for mid-size cars and SUVs. Common-rail with turbo, later versions as BlueHDi with SCR catalyst and AdBlue. Fundamentally robust and long-lasting with high torque. Injectors and the turbocharger are the main wear items. Timing belt with water pump should be replaced at least every 160,000 km. DPF regeneration becomes problematic with short-trip driving patterns.

• !! Timing belt snap caused by defective water pump from 90,000 km

  The plastic impeller of the water pump can disintegrate from as early as 50,000 km. Fragments enter the timing belt drive and cause the belt to snap with subsequent total engine destruction.

  Symptoms: Coolant temperature rises unusually, coolant loss without visible leak, faint grinding or squealing from the timing belt drive, sudden engine shutdown when belt snaps
  600–900 $
  Ad timing belt kit DW10 water pumpSKF VKMC 03259water pump 2.0 HDi
• !! Dual-mass flywheel wear from 130,000 km

  The dual-mass flywheel wears prematurely, especially on the 107 hp variant. Oil dilution from DPF regeneration accelerates wear. The clutch should always be renewed at the same time.

  Symptoms: Squealing or clattering when starting and stopping the engine, pronounced vibrations at idle, juddering when pulling away, knocking at low revs under load
  1,000–1,800 $
  Ad dual-mass flywheel 2.0 HDiLUK ZMS DW10Sachs ZMS Peugeot 307 2.0 HDi
• !! Leaking injectors causing oil dilution from 140,000 km

  Leaking injectors allow diesel into the engine oil, drastically reducing its lubricity. The rising oil level is often overlooked. This can cause piston and bearing damage.

  Symptoms: Diesel smell at the dipstick, oil level rises above maximum, strong exhaust smell inside the car, engine judders or knocks more than usual, increased fuel consumption
  400–1,500 $
  Ad fuel injector gasket DW10fuel injector 2.0 HDi BoschKupferdichtring fuel injector DW10

+ 6 more engine weaknesses + vehicle weaknesses

Top version of the PSA diesel family (2.2L HDi, 125-133 kW) for the 407, 607, and C5/C6. Strong and refined with excellent pulling power, but rare on the used car market. More involved maintenance than smaller HDi variants: double-row timing chain, variable geometry turbocharger, and complex timing belt replacement. With good care, a cultured long-distance engine capable of well over 300,000 km.

• !! Turbocharger bearing damage from oil starvation from 150,000 km

  The turbocharger bearings of the DW12 wear when oil quality is poor or change intervals are extended. Carbon deposits in the oil line block lubricant supply and cause turbo damage.

  Symptoms: Whistling from the turbo, blue smoke under acceleration, noticeable power loss, rising oil consumption
  800–2,000 $
  Ad turbocharger DW12 2.2 HDiturbo 407 2.2 HDiGarrett GT1549S
• !! Injectors seized in the cylinder head from 130,000 km

  Moisture accumulation in the injector bores causes the injectors to corrode into the cylinder head. Removal requires special tools and can result in consequential damage to the cylinder head.

  Symptoms: Rough engine running, increased fuel consumption, engine knocking, black smoke
  600–2,500 $
  Ad fuel injector DW12 2.2 HDifuel injector 407 2.2Bosch 0445110036
• !! EGR valve sticks from 100,000 km

  The EGR valve on the DW12 tends to stick from soot deposits, particularly during predominantly short-trip use. The mechanism gets stuck in the open or closed position and disrupts mixture preparation.

  Symptoms: Rough engine running, power loss, engine management light, hesitation under acceleration
  300–800 $
  Ad EGR valve DW12EGR valve 2.2 HDiPeugeot 407 EGR

+ 3 more engine weaknesses + vehicle weaknesses

The world's first series-production diesel hybrid (2.0L HDi front + 27 kW electric motor rear = all-wheel drive). Innovative technology with regenerative braking and electric AWD, but complex and maintenance-intensive. The high-voltage battery and power electronics are additional failure points. The diesel engine itself shares all DW10 weaknesses. Only service at specialized workshops — the combination of diesel and hybrid overwhelms many garages.

• !! Hybrid high-voltage battery capacity loss from 150,000 km

  The NiMH high-voltage battery of the Hybrid4 system loses capacity significantly after 8–10 years or 150,000 km. Below 70% residual capacity the system disables the electric drive. Replacement is extremely expensive.

  Symptoms: Electric drive mode no longer available, sharply declining EV range, hybrid warning light, increased diesel consumption
  2,500–6,000 $
  Ad Hybrid4 battery 3008NiMH battery Peugeot 508 Hybridhigh-voltage battery Hybrid4
• !! Inverter failure from 120,000 km

  The inverter that converts battery energy for the rear-axle electric motor can fail. Fault messages and power limitation follow. PSA carried out recall campaigns for affected model years.

  Symptoms: 'Hybrid System Fault' message, power limitation, no four-wheel drive, multiple warning lights on instrument cluster
  1,500–4,000 $
  Ad Inverter Hybrid4 Peugeotinverter 3008 Hybridpower electronics module Hybrid4
• !! Starter-generator bearing failure (Bosch SMG 138/80) from 100,000 km

  The high-voltage starter-generator Bosch SMG 138/80 is prone to bearing wear. Failed bearings seize the pulley, snapping the auxiliary belt — power steering, A/C, and alternator all drop out simultaneously. Peugeot specifies a reinforced stop/start (EST) belt; fitting a standard V-belt leads to much shorter service life.

  Symptoms: Squealing or grinding from engine bay, auxiliary belt snaps repeatedly, power steering and A/C fail simultaneously, charge warning light illuminates
  800–2,500 $
  Ad Bosch SMG 138/80 starter generator Hybrid4auxiliary belt EST stop/start 3008 Hybrid4pulley starter generator DW10

+ 6 more engine weaknesses + vehicle weaknesses

Turbo version of the Prince engine (1.6L THP 150, 110 kW) — notorious for timing chain problems in early production years (2007-2012). The chain stretches, skips, and causes valve damage. From 2013 onward with an improved chain tensioner, the situation improved significantly. Oil consumption from piston rings and valve carbon buildup are additional classic weak spots. Plan for high-pressure fuel pump and thermostat housing as wear items.

• !! Timing chain stretch — notorious main problem from 80,000 km

  The THP 150 is notorious for timing chain stretch. The hydraulic tensioner and plastic guide rails fail early. A jumped chain risks catastrophic engine damage. The problem particularly affects vehicles produced before 2013.

  Symptoms: Loud rattling/clattering on cold start, rhythmic knocking, power loss, fault codes P0016/P0017, poor cold starting
  700–4,000 $
  Ad timing chain EP6DT THP 150chain tensioner 1.6 THPtiming chain kit Peugeot 308 THPchainnführungsschiene EP6DT
• !! Extreme oil consumption from 80,000 km

  Many THP 150 engines consume alarmingly large amounts of oil from 80,000 km — sometimes 1 litre per 1,500–2,000 km. Causes are worn piston rings, turbocharger shaft seals and a defective crankcase ventilation system.

  Symptoms: Oil level drops rapidly, bluish smoke under acceleration, oil smell, frequent topping up required
  300–5,000 $
  Ad piston rings EP6DT THPPCV valve 1.6 THPcrankcase ventilation EP6DT
• !! Turbocharger failure and wastegate malfunction from 80,000 km

  The twin-scroll turbocharger of the THP 150 develops housing cracks from 60,000–80,000 km. The wastegate can develop leaks and lose the ability to hold boost pressure. Full turbocharger replacement is often required.

  Symptoms: Boost pressure missing, power loss, whistling noise, black/blue smoke, engine management light
  1,800–2,800 $
  Ad turbocharger EP6DT THP 150wastegate 1.6 THPturbocharger Peugeot 308 THP

+ 6 more engine weaknesses + vehicle weaknesses

Revised THP with 156 PS (115 kW) — slightly more powerful than the EP6DT. The timing chain remains the main problem: a full chain kit replacement costs 1,000-4,000 EUR depending on the extent of damage. Piston ring coking leads to increased oil consumption starting from 50,000 km. VVT solenoid valves clog from oil degradation. The turbocharger (Borgwarner K03) and high-pressure fuel pump are additional cost drivers. Only operate with short oil change intervals.

• !! Timing chain stretch and tensioner failure from 80,000 km

  The hydraulic chain tensioner jams or fails; the chain stretches from around 70,000–90,000 km. Rattling on cold start that briefly subsides after warm-up. Continued operation risks catastrophic engine damage from incorrect valve timing.

  Symptoms: Rattling on cold start at around 2,000–3,000 rpm, disappears after warm-up. In advanced stage: rattling on every cold start, engine management light
  1,000–4,000 $
  Ad 0816H9 timing chain kit EP6CDT9822827180 timing chain THP 156chain tensioner 1.6 THP 5FV
• !! Increased oil consumption due to coked piston rings from 80,000 km

  Piston rings coke up from deposits and lose their sealing effect. Oil consumption of 1 L/5,000 km is still considered normal by PSA; consumption above 1 L/1,000 km indicates compression problems. Poor oil quality or long oil change intervals are often the cause.

  Symptoms: Blue exhaust cloud on cold start or under load, dropping oil level between change intervals, smoke when revving
  1,500–4,500 $
  Ad 0640T4 piston rings EP6CDT Mahle0640T6 piston ring set 1.6 THPvalve stem seal THP 5FV
• !! High-pressure pump wears out prematurely from 90,000 km

  Design weakness of the HP pump: excessive pressure against the shaft seal leads to premature wear. Fault code P0087 (rail pressure too low) is the typical result. PSA acknowledged the problem and offered goodwill coverage up to 150,000 km / 7 years.

  Symptoms: Stumbling on cold start, fault P0087 (rail pressure too low), rail pressure 6–7 bar instead of 50 bar, engine runs normally again after restart
  320–800 $
  Ad 1920LL high-pressure fuel pump EP6CDT9819938480 HPFP THP 15613517588879 fuel pump 1.6 THP

+ 5 more engine weaknesses + vehicle weaknesses