QR25DER Hybrid Engine Service Repair Manual
The QR25DER Hybrid Engine Repair and Maintenance Manual includes detailed instructions for diagnosing, disassembling, repairing, and assembling the powertrain components. It provides diagrams and step-by-step instructions for performing tasks such as adjusting valves, replacing the timing belt, checking and replacing spark plugs, servicing the cooling system, and other important components. The manual also includes information on specific features of the hybrid system, such as interaction with the electric motor and battery, and tips for safely working with high-voltage components.
QR Engine Family: QR20DE, QR20DD, QR25DE and QR25DD.
Cars on which QR25DER 2.5 l was installed
Murano 3 (Z52) 2015 - 2016, Pathfinder 4 (R52) 2013 - 2016, QX60 1 (L50) 2013 - 2019
- Volume: 2488 cm³
- Engine features: Atkinson cycle
- Timing drive: chain
- Turbocharging: Eaton TVS compressor
- Oil: 5.8 liters 5W-30
- Compression ratio: 9.1
- Engine power: 234 (253)* hp
- Approximate resource: 250,000 km
- Fuel consumption: 8.7-10.9/100km
Frequent Breakdowns and Problems of the QR25DER Engine:
The QR25DER engine used in hybrid vehicles is known for its reliability, but like any engine, it has its own quirks and potential problems. Here are some things to look out for, as well as recommendations for proper maintenance:
Cooling System Issues: The QR25DER is prone to overheating if the cooling system is not working properly. This can be caused by radiator leaks, a faulty thermostat, or a faulty coolant pump. Overheating can warp the cylinder head and damage the gasket.
Timing Chain Wear: In some cases, the timing chain can stretch over time, causing the valve timing to fail and can cause serious engine damage.
EGR Valve Issues: The Exhaust Gas Recirculation (EGR) valve can become clogged, causing reduced engine efficiency and increased emissions.
Sensor Failures: Sensors such as the Mass Air Flow (MAF) sensor and Crankshaft Position sensor can fail, causing engine misfiring and poor performance.
Ignition System Problems: Spark plugs and ignition coils can wear out, causing misfires, rough running and loss of power.
Recommendations for Servicing the QR25DER engine:
Regular Oil and Filter Changes: Using high-quality oil and changing it regularly will help prevent wear on internal engine components and extend its life. It is also necessary to change the oil, air and fuel filters in a timely manner.
Checking and Maintaining the Cooling System: Regularly check the coolant level and condition, as well as the operation of the radiator, fan and thermostat. Replace the coolant according to the manufacturer's recommendations.
Replacing Spark Plugs: Monitor the condition of the spark plugs and replace them at the recommended intervals to ensure stable engine operation.
Checking the Timing Chain: If noise or vibration occurs from the timing chain, it is worth diagnosing and replacing the chain or tensioner if necessary.
Cleaning the EGR valve and throttle valve: Regularly cleaning these components will help maintain their functionality and improve engine performance.
Diagnostics and replacement of sensors: If errors occur in engine operation, such as unstable speed or deterioration in dynamics, it is recommended to conduct computer diagnostics to identify and replace faulty sensors.
Use of original spare parts: For engine maintenance and repair, it is recommended to use original or manufacturer-certified spare parts, which will ensure reliable operation and extend the service life of the engine.