Dual Valvetronic eccentric shaft sensors (one per bank) at 80,000 km: each bank has its own Valvetronic system; when one sensor fails it often signals the other is not far behind, causing limp mode and misfire on the affected bank. Replace both sensors together to avoid repeat labour, since access requires intake plenum removal on each bank.
Coolant hoses and expansion tank at 60,000 km: the V12 generates substantial heat; the plastic expansion tank cap and sensor can corrode, and the upper hose can collapse under vacuum when cold. Replace the expansion tank, cap, and rubber hoses preventively.
Valve stem seals (both banks) at 100,000 km: same Valvetronic-related heat-cycling issue as the N62, doubled across 12 cylinders; symptoms are blue smoke on startup/overrun and elevated oil consumption. Full valve stem seal replacement is an extremely labour-intensive specialist job.
Fuel injectors (12 units) at 80,000 km: high-pressure piezo injectors accumulate deposits, causing misfires, rough idle, and high fuel-trim corrections. Ultrasonic clean or replace all 12 together, and flow-test before condemning.
VANOS units (4 total — 2 per bank) at 120,000 km: seal wear and oil sludge on high-mileage engines cause camshaft timing errors on both banks, leading to hesitation and cold-start rattle. Reseal or replace all 4 VANOS units together with an oil system flush.
Timing chains (primary and secondary, both banks) at 150,000 km: the V12 has complex dual-chain timing with 4 VANOS phaser sprockets; guide failure on one bank can rapidly cascade. Fix: full 12-cylinder timing chain kit replacement.
Figures marked unconfirmed could not be cross-checked against a workshop source. Verify against the vehicle’s own documentation before tightening.
Service intervals
Oil Change Km
10000
Oil Spec
BMW Longlife-01 5W-30
Oil Capacity L
10.5
Spark Plugs Km
60000
Coolant Years
4
Air Filter Km
30000
Valve Clearance
Valvetronic — no adjustment
Special tools
BMW 11 9 260 — Valvetronic eccentric shaft locking set (need × 2 for both banks)
BMW 11 4 360 — V12 camshaft alignment tool set
BMW 11 0 300 — TDC pin
ISTA/P with N73 coding module for Valvetronic adaptation reset
BMW 11 8 560 — oil pressure test adapter
Pro tips from the field
The N73 shares much of its Valvetronic/VANOS/direct-injection-era architecture and failure modes with the N62 V8, doubled across two banks for 12 cylinders — most N62 failure points (Valvetronic sensors, VANOS, valve stem seals, timing chain) recur here, roughly doubled in labour.
Any N73 purchase inspection must include a compression test on all 12 cylinders — low compression on even one cylinder makes the repair uneconomical for most owners
Valvetronic adaptation is MANDATORY after any sensor or motor replacement — skip this and the engine will idle poorly regardless of the new parts
These cars are cheap to buy for a reason: specialist independent shops with BMW V12 experience are rare; always pre-agree labour rates per hour before disassembly
Oil quality is not negotiable — N73 owners who used anything other than BMW LL-01 5W-30 report earlier VANOS and chain guide failures.
Got a N73B60 problem? Ask for free.
Describe the symptoms — TorqFix replies with a diagnosis cited from verified workshop data.
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
