Models · Audi
Audi SQ7 4M buying guide
The SQ7 arrived in 2016 as a seven-seat performance SUV with a 4.0-litre V8 diesel boosted by two turbos and an electric compressor. In 2020 a 4.0 twin-turbo V8 petrol replaced it. The checks below are mainly for the diesel.
The versions
- 4.0 TDI V8 diesel (2016 to 2020): 435PS and 900Nm, with two turbos and an electrically powered compressor on a 48V system
- 4.0 TFSI twin-turbo V8 petrol from 2020: 507PS
- ZF 8-speed torque converter automatic with quattro
- Adaptive air suspension as standard
- Optional Driving Dynamics pack: sport rear differential, all-wheel steering and an electromechanical anti-roll system
What to check on a SQ7
3 model-specific things to look at when you view one. They're a starting point, not the full inspection.
The electric compressor
What to look for: On a diesel, pull away briskly from a standstill and feel for strong, instant response. Check the start-stop system works when the engine is warm. Ask whether the electric compressor has ever been replaced, and note any engine warning light.
Why it matters: The electric compressor runs off a 48V system with a lithium-ion battery under the boot floor and fills in before the turbos build boost. Poor step-off and a start-stop system that has stopped working are the main signs it has failed; a diagnostic check will show its fault code (P15B700).
Air suspension compressor
What to look for: Look at the car from each corner after it has stood, before it's started. It should sit level. With the engine running, raise and lower it through the modes and listen for the compressor running for a long time.
Why it matters: Air suspension is standard, and later 2019 to 2020 cars could suffer air suspension failure, usually related to the compressor. A car that holds its height overnight and moves through the modes promptly is in good order.
Oil leaks and the oil level
What to look for: With a torch, look around the top of the engine at the valve covers, underneath at the sump, and around the oil filter housing for wet oil. Check the oil level and ask whether the car has ever shown an excess oil warning.
Why it matters: Oil can leak from the valve covers, sump or oil filter housing on the V8 diesel. An excess oil warning can come from diesel fuel diluting the oil, so it needs investigating.
Also in the full guide
- Gearbox shifting delays
- Suspension bushes and driveshaft boots
- Diesel emissions parts and knock sensors
- The cold start, test drive and paperwork checks for the exact version you're viewing
The full guide to the SQ7
The CrankSight guide walks you round the car on your phone at the viewing, with every check for the exact version you're looking at: what to look for, where to find it, and what anything you find is likely to cost. As you go it builds an assessment of that car, and if you view more than one, it lines them up side by side.
£29 for the model, used on as many cars as you like, delivered within 72 hours or your money back.
General points for the model, last checked October 2026. Every car is different, so treat this as a guide to what to look at, not a verdict on any car. CrankSight is independent and has no connection with Audi.