Nissan Skyline: VR30DDTT Valve Stem Seal Oil Consumption

The VR30DDTT twin-turbo 3.0-litre engine suffers from accelerated valve stem seal degradation, causing engine oil to be drawn past the seals into the combustion chamber during deceleration and cold starts. Affected engines can consume 0.5–1 litre per 1,000 km well before service intervals, with blue smoke typically visible on cold morning starts and on overrun. Nissan issued TSB NTB18-043 addressing oil consumption on this engine family. The root cause is premature hardening and wear of the valve stem seals, exacerbated by high under-bonnet temperatures from the twin-turbo configuration. Left unaddressed, catalytic converter fouling and spark plug fouling follow.

• Blue-grey smoke from exhaust on cold start that clears after warm-up
• Blue smoke puff from tailpipe on sharp throttle lift-off or engine braking
• Oil level drops noticeably between service intervals with no external leaks
• Fouled spark plugs with oil deposits on electrode
• Catalytic converter smell or early converter failure due to oil contamination

1. 1

   Check the engine oil level against the service record interval and ask owner how often oil is topped up.

2. 2

   Start the engine cold and watch exhaust for blue smoke.

3. 3

   Rev the engine to 3000 rpm then lift off sharply and observe tailpipe for puff of blue smoke on overrun.

4. 4

   Inspect the spark plugs for oil fouling if accessible.

5. 5

   Request any dealer oil consumption test documentation.

Parts involved: Catalytic converter, Turbocharger.

$1,800 to $4,200 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “How many litres of oil have you added between the last two services, and what is the mileage between those services?”
• “Has Nissan or a dealer performed an oil consumption test under TSB NTB18-043, and what was the result?”
• “Is there any history of spark plug replacement due to oil fouling?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.