E65 745i N62 — VANOS problems, valve stem seals, and oil consumption fixes
The E65 7 Series with the N62 4.4L V8 is a fantastic luxury car that can be bought for very little money. But the N62 engine has several well-known issues that you need to address.
The big three N62 problems:
VANOS solenoid failure — causes rough idle, loss of power, and fault codes. The eccentric shaft sensor also fails frequently. Replacement cost: 500-800 EUR for both banks.
Valve stem seal failure — the N62 is notorious for oil consumption caused by hardened valve stem seals. Symptoms include blue smoke on startup and oil consumption of 1L per 1000km or more. Repair requires removing the cylinder heads: 3000-5000 EUR.
Coolant transfer pipe — similar to the N63, the N62 has a coolant pipe that runs through the valley of the engine. When it leaks, coolant mixes with oil. Replacement: 1500-2500 EUR.
Despite these issues, the N62 is a smooth and powerful engine when properly maintained. The 745i makes 333hp and has effortless highway cruising ability. Used E65s can be found for 3-8k EUR, making them incredible value if you are prepared for the maintenance.
The key is to buy one that has already had the major work done, or budget for it in your purchase price.