Renault R9M 1.6 dCi Injector Problems: Symptoms & Repair (UK)

The R9M replaced the M9R as Renault/Nissan's mid-range diesel. Found in the Qashqai J11, Kadjar, and Scenic Mk4. Unlike older Renault diesels, the R9M uses Bosch (not Delphi) common-rail injection.

Common R9M injector failure symptoms

• Rough idle and vibration: Injector imbalance on the refined R9M is easily noticeable.
• DPF regeneration issues: Poor combustion from worn injectors accelerates DPF soot loading.
• Power loss in Sport mode: ECU limits output when injector deviation is detected.

Why R9M injectors fail

• fuel contamination
• high-pressure wear cycles
• carbon buildup
• poor fuel quality
• internal valve wear

How to diagnose R9M injector faults

1. Read fault codes: Connect an OBD-II scanner and note any injector-related codes (P0201–P0204, P2146, P2149). This identifies which cylinder is affected.
2. Perform a leak-off test: Disconnect the fuel return pipes and route into measuring containers. Run the engine at idle for 60 seconds. Compare volumes per cylinder against manufacturer spec.
3. Listen for injector tick: Use a mechanic's stethoscope on each injector body. A dead or irregular tick indicates a stuck or failing solenoid.
4. Check fuel rail pressure: Monitor live fuel rail pressure data via diagnostic tool. Low pressure can mimic injector symptoms and may indicate a fuel pump issue instead.
5. Inspect for external leaks: Check around injector seals for signs of fuel or combustion gas leakage. Black carbon deposits indicate a blown seal.
6. Cylinder balance test: Use diagnostic software to run a cylinder contribution test. This electronically disables each injector in turn to measure its effect on engine speed.

Fault codes linked to R9M injector issues

• P0201-P0204 – Injector circuit malfunction
• P2002 – DPF efficiency below threshold

R9M repair advice

R9M uses Bosch injectors — IMA coding via Renault CLIP or Nissan Consult is required. The R9M is also found in the Mercedes Citan badged as the OM607.

R9M injector replacement cost (UK)

• Per injector: £180 - £350
• Full set: £700 - £1,200
• Labour: £120 - £300

Compatible injector part numbers for R9M

• Bosch 0445110414 – Bosch injector for R9M
• Renault 166006212R – Renault OE reference

Vehicles using the R9M engine

• Nissan Qashqai (2013-2019)
• Renault Kadjar (2015-2019)
• Renault Scenic (2016-2019)
• Mercedes-Benz Citan (2013-2019)

Find your exact R9M injector by registration

Frequently asked questions

Does the R9M use Bosch or Delphi injectors?

Bosch. The R9M switched from Delphi (used on older K9K engines) to Bosch common-rail.

How much does R9M injector replacement cost?

A set of four costs £400-£700. Labour is 2-3 hours.

How much does it cost to replace injectors?

Replacement typically costs £150–£350 per injector depending on brand and engine. A full set of four with professional fitting usually costs £600–£1,200.

Can I drive with a faulty injector?

Driving with a faulty injector can cause engine damage, increased fuel consumption, DPF contamination, and oil dilution. We recommend diagnosis and replacement as soon as possible.

Do new injectors need coding?

Some vehicles require injector coding after replacement using manufacturer-specific diagnostic tools. Many Bosch solenoid units are plug and play. Check your engine guide for specific requirements.