Renault Scenic Mk2 1.9 dCi

The F9Q 1.9 dCi turbo is known for seal failures, often linked to a sticking oil pressure relief valve in the oil pump. When this valve gums up, excessive oil pressure blows seals out of the turbo or oil filter housing. Early signs include blue/white smoke on startup or under boost, and rising oil consumption (watch for anything above 0.5 litre per 1,000 km). On early 2003-2004 models, a design issue caused turbo failures below 80,000 km. A reconditioned turbo fitted by a specialist costs around €600-800, while a new OEM turbo with fitting runs €1,200-1,800. Preventive measures include regular oil changes with quality synthetic oil and checking the oil pressure relief valve during servicing.

This is one of the most common faults on the Scenic Mk2. The fully digital instrument cluster suffers from dry solder joints and capacitor degradation. Symptoms start with flickering backlighting and progress to random resets of the clock, trip computer, and odometer readings (which can add up to 1,000 phantom miles). Eventually the display may go completely dark. Renault dealerships charge €400-500 for replacement, but specialist repair services can resolder the connections for €100-200. This fix typically lasts several years. Nearly all Scenic Mk2s will develop some degree of dashboard issues over their lifetime.

The Scenic Mk2 was one of the first mainstream cars with an electronic parking brake, and the system is not entirely reliable. Common failures include the EPB not releasing (requiring a manual override to drive), not engaging at all, or displaying persistent warning messages. The control module circuit board is the usual culprit. Renault dealers charge €600-800 for a replacement module plus fitting, but specialist electronic repair services can rebuild the module for €100-200. The caliper motors themselves can also seize, particularly if the car has been standing for extended periods. Renault issued a recall for the EPB system on some early production cars.

The EGR valve on the F9Q engine is prone to carbon and soot buildup, particularly if the car does a lot of short urban trips. A clogged EGR valve causes rough idling, stalling at low speed, and noticeable power loss. If the valve sticks closed, the engine can overheat; if it sticks open, excess exhaust gas recirculation can accelerate turbo wear. Cleaning the valve costs €100-200 at an independent garage. Full replacement with a new valve and gasket runs €350-600 including labour. The valve is relatively accessible on the F9Q engine (about 60-90 minutes of work), though it requires removal of the scuttle panel area components.

The Bosch common rail injectors on the F9Q engine can fail due to carbon buildup or internal seal wear. They tend to fail in pairs (cylinders 1 and 3, or 2 and 4). Symptoms include rough running, excessive smoke, a persistent 'Check Injection' warning, and poor fuel economy. A single reconditioned injector costs around €150-200 fitted, while a full set of four new injectors with coding runs €1,000-1,500 at an independent diesel specialist. Renault dealer quotes are significantly higher, often €2,500+. The fuel system is generally robust with the Bosch components, and injector failure typically occurs beyond 150,000 km.

Models from mid-2005 onwards were fitted with a DPF that uses a fifth injector in the exhaust to initiate active regeneration. Frequent short trips prevent the regeneration cycle from completing, gradually blocking the filter. The thin rubber pressure sensor hoses connecting the differential pressure sensor are another common failure point, causing false warnings. A forced regeneration at a garage costs €150-300. DPF cleaning is €300-500. Full DPF replacement costs €800-1,200. Early Scenic Mk2 models (2003-early 2005) were not fitted with a DPF, which simplifies ownership considerably.

Window regulator failure is extremely common across the Scenic Mk2 range. The plastic guide clips break, the Temic electronic control module on the motor corrodes from moisture ingress, or the regulator mechanism simply wears out. Symptoms range from erratic operation (windows opening by themselves) to complete failure with the glass dropping inside the door. Renault extended the warranty on window regulators to 4 years due to the high failure rate and issued a recall for the plastic guides. Independent repair costs €150-250 per window, while Renault dealers charge €300-400.

The heater blower resistor and its wiring connector are prone to overheating and eventually burning out on the Scenic Mk2. Symptoms include certain fan speeds not working (typically speeds 1-3 fail first while speed 4 remains), a burning smell from the ventilation system, and in some cases visible melting of the connector. Renault released an upgraded resistor with doubled-up connector pins to improve current handling. Replacement of the resistor alone costs €50-100 at an independent, but the wiring loom connector must also be replaced (an additional €50-100 for parts). A Renault dealer charges €250-350 for the complete repair.

The Scenic Mk2 is prone to water entering the cabin through blocked drainage channels under the scuttle panel or around the sunroof (on equipped models). Debris collects in the drainage channels and causes water to overflow directly into the interior, typically the passenger footwell first. If caught early, clearing the drains and drying the carpet costs very little. However, prolonged water ingress can damage the wiring loom, corrode ECU connectors, and cause persistent electrical faults that are difficult and expensive to trace. Always check under the carpets for dampness before buying. Sunroof drain tubes that exit behind the front wheel arch should be checked and cleared regularly.