What Peugeot codes (P0234, P0420, P0401, P0203, P0106, P0100) actually mean on Peugeot engines — the real cause, the common misdiagnosis, and the honest UK repair cost.
These are the OBD fault codes we see most often on Peugeot vehicles in the workshop, with the real cause on Peugeot engines rather than the generic textbook definition, plus the honest independent-garage cost.
Peugeot fault codes explained
- P0234 — Turbo overboost on Peugeot 1.6 / 2.0 HDi — usually the wastegate actuator or VGT sticking from carbon, not the turbo itself. Typical UK cost £180–£1400.
- P0420 — Catalyst efficiency on Peugeot petrol — 1.2 PureTech and older 1.6 VTi often have lambda drift before genuine cat failure. Typical UK cost £140–£750.
- P0401 — EGR flow insufficient on Peugeot 1.6/2.0 HDi (PSA DV6/DW10) diesels — sticking EGR valve or clogged FAP/DPF causing back-pressure. Typical UK cost £180–£720.
- P0203 — Injector circuit Cylinder 3 on Peugeot 1.6/2.0 HDi — Siemens/Continental piezo injectors fail with age, plus chronic injector seal blow-by. Typical UK cost £220–£780.
- P0106 — MAP sensor performance on Peugeot 1.6 THP/1.6 HDi — shared PSA/BMW Prince engine MAP failure and HDi charge-pipe splits. Typical UK cost £100–£380.
- P0100 — MAF circuit malfunction on Peugeot 1.6/2.0 HDi and 1.6 THP — MAF contamination from EGR and oily breather very common. Typical UK cost £100–£320.
- P244A — DPF differential pressure too low on Peugeot HDi — Eolys additive system & pressure pipes are the usual culprits. Typical UK cost £160–£1600.
- P0299 — Turbo underboost on Peugeot HDi and PureTech — VGT actuator carbon-up on diesels, wastegate solenoid on PureTech petrol. Typical UK cost £160–£1500.
- P0171 — System too lean on Peugeot — PSA THP and PureTech engines have known PCV and intake gasket weaknesses. Typical UK cost £180–£700.
- P0016 — Crank/cam correlation Bank 1 on Peugeot — 1.6 THP Prince engine timing chain stretch (208 GTi, 308, RCZ). Typical UK cost £600–£2400.
- P2002 — DPF efficiency below threshold on Peugeot HDi — clogged DPF and Eolys fluid empty on 1.6/2.0 HDi. Typical UK cost £140–£1400.
- P0341 — Camshaft position sensor performance on Peugeot — 1.6 HDi DV6 sensor degrades with engine heat. Typical UK cost £65–£280.
- P0011 — VVT 'A' over-advanced Bank 1 on Peugeot — 1.6 THP Prince VVT solenoid and chain stretch (208 GTi/308/RCZ). Typical UK cost £60–£2400.
- P0087 — Fuel rail pressure too low on Peugeot — 1.6/2.0 HDi lift pump and Bosch DRV failure. Typical UK cost £180–£1400.
- P2463 — DPF soot accumulation on Peugeot HDi — Eolys-additive system failure and over-soot. Typical UK cost £140–£1400.
Codes are generic across manufacturers, but the fix is not. The same code on a Peugeot usually points at a different component than it would on another make, which is why a make-specific diagnosis saves money before any parts are bought.