The new Audi SQ5 TDI diesel features a powerful V6 engine with a mild hybrid systems and an electric powered compressor to ensure that maximum torque is available to the sporty SUV at just above idle.
The 3.0 V6 TDI engine delivers 255 kW (347 hp) and 700 N·m (516.3 lb-ft), with the torque available continuously across a broad range from 2,500 to 3,100 rpm. The V6 diesel accelerates the sports SUV to highway speed in 5.1 seconds on its way to an electrically limited top speed of 250 km/h (155.3 mph). In the NEDC it consumes between 6.6 – 6.8 liters of diesel per 100 kilometers (35.6 – 34.6 mpg US), corresponding to 172 – 177 grams of CO2 per kilometer (276.8 – 284.9 g/mi). The SQ5 TDI is certified according to the Euro 6d-temp emission standard.
Audi has systematically refined the drive concept from the full-size SQ7 TDI for the new SQ5 TDI. The 48-volt main electrical system includes an electric-powered compressor (EPC) and a mild hybrid system. Energy is stored in a compact lithium-ion battery with an electrical capacity of 10 Ah located beneath the luggage compartment floor. An AC/DC converter connects the conventional 12-volt electrical system.
The electric compressor is the ideal assistant for the turbocharger. It helps out whenever the exhaust gas flow provides too little energy to drive the turbocharger, i.e. when starting off and accelerating in the low-rev range up to 1,650 rpm. High torque is available immediately with no turbo lag whenever the driver needs it, whether starting off, passing or exiting a curve. In everyday driving situations, the early and rapid torque development made possible by the technology keeps revs and fuel consumption low.
The electric powered compressor is located in the intake air path downstream of the intercooler and close to the engine. If the load demand from the accelerator is high but there is still too little boost from the turbocharger, the EPC comes into play. A compact electric motor with an output of 7 kW accelerates the compressor wheel to 65,000 rpm in roughly 300 milliseconds, producing a relative boost pressure of 1.4 bar.
The MHEV system (mild hybrid electric vehicle) in the new Audi SQ5 TDI can reduce real-world fuel consumption by as much as 0.7 liters per 100 kilometers. At its core is a belt alternator-starter (BAS) connected to the crankshaft. During deceleration, it can recuperate up to 12 kW of energy. This electrical energy is stored in the lithium-ion battery, from where it is dynamically distributed to the consumers in the electrical system.
If the driver lifts off the accelerator at a speed between 55 and 160 km/h (34.2 and 99.4 mph), the new Audi SQ5 TDI can, depending on Audi drive select setting and driving situation, either recuperate, roll at idle with the clutch disengaged or coast with the engine off for up to 40 seconds.
The BAS restarts the engine the next time the accelerator is depressed, and that noticeably faster and more smoothly than a conventional starter. MHEV technology allows for start/stop operation at a speed of up to 22 km/h (13.7 mph). If the vehicle is equipped with the adaptive cruise control (ACC), the engine restarts while the brake pedal is still depressed as soon as the vehicle in front of the SQ5 TDI begins to move.
This top output version of the 3.0 V6 TDI engine has been further developed and modified in numerous areas. Crankshaft, pistons, connecting rods and oil management have all been specially configured for the more stringent demands. The thermal management system is highly versatile. The crankcase and the cylinder heads have their own cooling circuits, allowing the engine oil to warm up quickly after a cold start. The coolant flow is directed to the oil cooler, the EPC, the BAS and the turbocharger as needed. The large exhaust gas turbocharger with variable turbine geometry (VTG) produces a relative boost pressure of up to 2.4 bar. A sound actuator in the exhaust system gives the TDI a sonorous sound.
A fast and smooth-shifting eight-speed tiptronic handles the power transmission. Its lower gears feature short, sporty ratios, while the upper gears are long to reduce revs and fuel consumption. New detailed solutions enable the tiptronic to work effectively with MHEV technology. If the sport SUV is rolling and the engine is idling or shut off entirely, a clutch in the central transmission opens and interrupts the power connection. An electric oil pump enables the tiptronic to engage the gear while coasting that will be needed at restart.
Like every S model from Audi, the new SQ5 TDI comes standard with quattro permanent all-wheel drive. In normal driving conditions, its self-locking center differential distributes torque between the front and rear axle in a 40:60 ratio. When slip is detected, the majority of the power is directed to the axle with the better traction. Depending on the driving situation, a maximum of 70 percent can flow to the front or 85 percent to the rear.
Wheel-selective torque control, an intelligent software function complementing the quattro drive, is active on all kinds of surface. During dynamic cornering, it brakes the wheels on the inside of the curve minimally before they begin to slip. The power is thus directed via the differential to the wheel with the better traction. The sports SUV turns into the curve ever so slightly. Its self-steering behavior remains neutral for a long time, and handling remains stable, precise and agile.
Customers can also order the SQ5 TDI with a sport differential on the rear axle. It actively distributes the power between the rear wheels during dynamic cornering. The sport differential literally pushes the car into the curve, nipping understeer in the bud. It sends more torque to the outside rear wheel when accelerating out of tight radii to further improve agility.
The new Audi SQ5 TDI offers a broad portfolio of driver assistance systems. The predictive efficiency assistant provides specific tips to help the driver save fuel. Audi active lane assist makes it easier to stay in your lane and can handle some of the steering task in slow-moving traffic. The distance warning display alerts the driver when the distance to the vehicle ahead drops below a safe distance. These and other functions are brought together in the optional Tour assist package.
The optional functions rear cross traffic assist, exit warning, collision avoidance assist and turn assist also enhance safety in everyday driving. The same applies to the pre sense systems; Audi pre sense city comes as standard. It warns the driver about pedestrians and vehicles, and if necessary initiates automatic emergency braking within system limits. Park assist, camera-based traffic sign recognition and hill descent control round out the optional features.
The new Audi SQ5 3.0 TDI will begin arriving at German dealerships in Summer 2019 and have a base price of €67,750.