Bob's Mechanical Repairs

Ford Fault Codes — Real Causes, Fixes & UK Costs

Bob's Mechanical Repairs — independent family-run garage in Birnam, Dunkeld, Perthshire. Call 01350 727 276 or email [email protected].

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What Ford codes (P0299, P0420, P132B, P0401, P0301, P0203) actually mean on Ford engines — the real cause, the common misdiagnosis, and the honest UK repair cost.

These are the OBD fault codes we see most often on Ford vehicles in the workshop, with the real cause on Ford engines rather than the generic textbook definition, plus the honest independent-garage cost.

Ford fault codes explained

  • P0299 — Turbo underboost on Ford 1.0 EcoBoost and 1.5/1.6 TDCi — usually the actuator linkage or a split charge pipe, not the turbo itself. Typical UK cost £180–£1400.
  • P0420 — Catalyst efficiency below threshold on Ford petrols — on EcoBoost engines this is often a cracked exhaust manifold rather than a worn cat. Typical UK cost £180–£950.
  • P132B — Turbocharger boost control 'A' performance — almost always the small turbo actuator on Ford 1.0 EcoBoost. Typical UK cost £400–£1500.
  • P0401 — EGR flow insufficient on Ford diesels — carbon-blocked EGR cooler or valve, especially on short-trip vehicles. Typical UK cost £180–£650.
  • P0301 — Cylinder 1 misfire on Ford petrol — coil pack and plug first, then the well-known wet-plug issue on 1.6 EcoBoost. Typical UK cost £60–£1800.
  • P0203 — Injector circuit malfunction Cylinder 3 on Ford — usually a failed injector or chafed wiring loom on TDCi/EcoBoost engines. Typical UK cost £180–£580.
  • P0106 — MAP sensor range/performance on Ford EcoBoost/TDCi — usually a contaminated sensor or boost-leak rather than the sensor itself. Typical UK cost £80–£380.
  • P0562 — System voltage low on Ford — almost always a failing alternator, weak battery or corroded earth strap on EcoBoost/TDCi models. Typical UK cost £120–£520.
  • P0100 — MAF circuit malfunction on Ford — contaminated or failed Hitachi/Bosch MAF sensor very common on TDCi/EcoBoost; rarely the wiring. Typical UK cost £80–£280.
  • P0304 — Cylinder 4 misfire on Ford — coil-pack failure on EcoBoost, glow-plug/injector on TDCi, or carbon-fouled plug on Duratec. Typical UK cost £80–£480.
  • P0128 — Coolant below thermostat regulating temperature on Ford — almost always a stuck-open thermostat, not a sensor fault. Typical UK cost £90–£240.
  • P0300 — Random misfire on Ford petrols — on EcoBoost engines almost always coils or low-tension wiring, on Duratec usually plugs at end of life. Typical UK cost £80–£380.
  • P0741 — Torque converter clutch stuck off on Ford auto / PowerShift — usually solenoid pack or low / contaminated ATF, not the converter itself. Typical UK cost £280–£1100.
  • P244A — DPF differential pressure too low on Ford TDCi — usually a blocked pressure pipe or a cracked / missing DPF substrate, not 'no DPF needed'. Typical UK cost £140–£1800.
  • P0016 — Crankshaft/camshaft correlation fault on Ford — almost always wet-belt failure on 1.0 EcoBoost or stretched chain on 1.6 TDCi. Typical UK cost £600–£2800.
  • P0606 — PCM/TCM processor fault on Ford — on PowerShift cars it's the TCM, on EcoBoost it can be a software corruption or a corroded PCM ground. Typical UK cost £220–£1600.
  • P0087 — Fuel rail pressure too low on Ford TDCi — usually a tired high-pressure pump or a leaking injector return on common-rail diesels. Typical UK cost £140–£1800.
  • P2463 — DPF soot accumulation on Ford TDCi — usually short-trip driving that prevents successful regeneration cycles. Typical UK cost £90–£1800.
  • P0234 — Turbocharger overboost on Ford EcoBoost — usually a stuck wastegate actuator or boost-control solenoid fault. Typical UK cost £160–£1200.
  • P0341 — Camshaft position sensor 'A' range/performance on Ford — sensor failure on EcoBoost, wiring harness on TDCi. Typical UK cost £60–£850.
  • P0455 — EVAP system gross leak on Ford — almost always a loose or damaged fuel cap, but on EcoBoost the purge valve also fails commonly. Typical UK cost £25–£350.
  • P2002 — DPF efficiency below threshold on Ford — substrate damage or ash overload after repeated failed regens. Typical UK cost £180–£1900.
  • P0017 — Crank to exhaust cam correlation on Ford — wet-belt jump on 1.0 EcoBoost or chain stretch on 1.6 TDCi. Typical UK cost £600–£2800.
  • P0014 — Exhaust cam over-advanced on Ford — Ti-VCT solenoid failure on EcoBoost and Duratec petrols. Typical UK cost £90–£750.
  • P0193 — Fuel rail pressure sensor high on Ford — EcoBoost HPFP sensor and 2.0/2.2 TDCi rail sensor failures. Typical UK cost £140–£850.
  • P0340 — Camshaft position sensor circuit on Ford — failing CMP sensor on 1.6/2.0 TDCi and 1.0 EcoBoost wet-belt debris damaging the reluctor. Typical UK cost £60–£2200.
  • P0571 — Brake switch A circuit on Ford — cruise/start-stop drops and brake-light fault from the dual-stage brake switch on Focus/Fiesta/Mondeo. Typical UK cost £25–£90.
  • P2563 — Turbo boost control position sensor on Ford — VGT actuator electronic feedback fault on 2.0/2.2 TDCi Transit and Mondeo. Typical UK cost £280–£1600.
  • P2279 — Intake air system leak on Ford — perished dump valve diaphragm or split silicone elbow on 1.0/1.5/1.6 EcoBoost. Typical UK cost £35–£280.
  • P1340 — Camshaft position sensor B circuit on Ford — Ti-VCT solenoid sticking with sludge on 1.6/2.0 Duratec & Sigma. Typical UK cost £90–£380.
  • P0507 — Idle speed higher than expected on Ford — vacuum leak via dump valve or PCV on 1.0/1.5/1.6 EcoBoost. Typical UK cost £35–£280.
  • P0430 — Bank 2 cat efficiency on Ford 2.5 V6 / 3.0 V6 Duratec (Mondeo, S-Max, Galaxy ST220) — aging cat and rear O2 sensor drift. Typical UK cost £220–£1200.
  • P0011 — VVT 'A' over-advanced Bank 1 on Ford — Ti-VCT solenoid sludge or wet-belt damage on 1.0/1.5/1.6 EcoBoost and 1.6 Ti-VCT. Typical UK cost £90–£2400.
  • P0089 — Fuel pressure regulator on Ford — 1.6/2.0 TDCi rail pressure control valve failure and Bosch CP4 on 2.2 TDCi Transit. Typical UK cost £160–£1600.
  • P0410 — Secondary air injection malfunction on Ford — 1.6/2.0/2.5 Duratec SAI pump on Focus/Mondeo (US-spec mainly, but UK imports). Typical UK cost £140–£480.
  • P0030 — Upstream O2 sensor heater open circuit on Ford — usually a corroded connector at the sensor tail, not the sensor itself. Typical UK cost £60–£280.
  • P0036 — Downstream O2 heater fault on Ford — post-cat sensor loom chafes on the exhaust hanger or heat shield. Typical UK cost £60–£220.
  • P0402 — EGR flow excessive on Ford diesel — sticking EGR valve stuck open, carbon-loaded on 1.6/2.0 TDCi. Typical UK cost £180–£850.
  • P0130 — Upstream O2 sensor circuit fault on Ford — signal wire chafe or lazy sensor on high-mileage EcoBoost. Typical UK cost £75–£320.
  • P242F — DPF ash accumulation limit reached on Ford diesel — DPF at end of life, not a regen issue. Typical UK cost £650–£1900.
  • P0421 — Warm-up catalyst efficiency below threshold on Ford — usually a lazy downstream sensor before it's actually the cat. Typical UK cost £140–£900.

Codes are generic across manufacturers, but the fix is not. The same code on a Ford 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.

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