SevereAffected: 2007-201280,000–150,000 miles

BMW 3 Series E90 320d N47 2.0d 177bhp — Diesel Particulate Filter (DPF) Blockage

A blocked DPF on the N47 is highly common, often a secondary symptom of thermostat failure, glow plug module failure, or exclusively urban driving.

Severity

Severe

DIY Difficulty

Professional Only

Est. Cost

£250–£1500

OBD Codes

480A481A

Component Diagram

DPF

Typical layout and location for the DPF assembly.

Reference Illustration

Symptoms

CC-ID 71 or DPF warning symbol on iDrive
Sluggish acceleration and limp mode
Whistling noise from turbo (excess backpressure)
Fault codes 480A and 481A

Root Cause

Soot accumulation exceeds the DPF's capacity. Active regeneration is blocked if coolant temperature is too low, glow plug controller is faulty, or fuel level is below 1/4 tank.

How To Fix

Address root cause first (thermostats or glow plug module)
Attempt forced regeneration via Carly or ISTA
Professional chemical clean (£250-350)
Replacement DPF if cracked or melted internally (£800-1,500)

Estimated Repair Costs

Repair Option	Est. Cost (GBP)
DIY (parts only)	£100–£600
Independent Garage	£250–£1500
Main Dealership	£400–£2400

Other Faults on This Variant

N47 Timing Chain Failure (Rear of Engine)

Critical

2007-201280,000–160,000 miles£2000–£3500

The BMW N47 diesel engine has a timing chain positioned at the REAR of the engine, against the bulkhead. Chain failure is catastrophic, and repair requires engine removal. This is the most significant known fault in the BMW 3 Series range.

Swirl Flap Failure and Engine Ingestion

Critical

2007-201260,000–120,000 miles£30–£5000

The N47 intake manifold has metal swirl flaps on actuator rods. When the rods corrode and snap, the flap breaks off and gets ingested into the engine, causing severe internal damage.

EGR Cooler and Valve Failure

Moderate

2007-201270,000–130,000 miles£600–£1200

EGR cooler failure on the N47 is common from 70,000 miles. Coolant leaks into the intake manifold and the EGR valve sticks, causing power loss and rough running.

Disclaimer: Repair cost estimates are indicative and based on community data. Always get a quote from a qualified mechanic before proceeding with any repair.