Toyota Voxy: 3ZR-FAE Excessive Oil Consumption via Valve Stem Seals

The 3ZR-FAE engine fitted to ZRR70 Noah models is documented to consume engine oil at above-normal rates as mileage accumulates, primarily due to hardening and shrinkage of the valve stem seals on both intake and exhaust valves. As the seals lose elasticity they allow oil to be drawn down the valve stems into the combustion chamber during the intake stroke and during overrun deceleration. This produces characteristic blue-grey smoke on startup and on trailing throttle. Oil consumption rates of 1 litre per 1,500–3,000 km are common on high-mileage examples. The repair requires a full valve stem seal replacement with the head on the engine, using a compressed-air lock on each cylinder.

• Blue-grey smoke from exhaust on cold startup, clearing within 30–60 seconds of running
• Blue smoke visible in the rearview mirror when lifting off throttle at highway speed
• Engine oil level 1–2 litres low between 5,000 km service intervals with no external leaks
• Spark plugs showing black, oily fouling on tip and electrode

1. 1

   Check engine oil level — low level relative to recent top-up interval is a red flag.

2. 2

   Start cold engine and observe exhaust for blue smoke on initial start and during first 30 seconds of running.

3. 3

   Road test: lift off throttle from 80 km/h and watch exhaust for blue puff as engine braking begins.

4. 4

   Inspect spark plugs for oil fouling (black oily deposits on electrode).

5. 5

   Ask seller how often oil needs to be topped up between service intervals.

≈A$640 to ≈A$1,290 at independent workshop rates, shown as an approximate guide in Australian dollars. That is for this job on its own, not for the car.

An estimate, converted to Australian dollars, 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 often do you need to add oil between services?”
• “Is there any blue smoke visible on startup or when lifting off the accelerator?”
• “When were the spark plugs last replaced, and were they oil-fouled?”

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.