MajorCommonEngine

Subaru Impreza: EJ15 Valve Stem Seal Deterioration and Oil Burning

EJ15 Valve Stem Seal Deterioration and Oil Burning is a common engine fault on the Subaru Impreza on the 2000–2011 cars, and we rate it major. Putting it right costs $700 to $1,600 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 44 documented faults on the Subaru Impreza.

Vehicle: Subaru Impreza
Engine: EJ15
Years: 2000–2011
Fuel: petrol
System: Engine

This page covers the Subaru Impreza as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Subaru Impreza faults44 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph for this fault yet. We would rather show none than show a picture of something else.

What goes wrong

The EJ15 1.5-litre boxer engine fitted to base-grade GD and GE/GH Imprezas develops oil burning as the rubber valve stem seals harden and shrink with age. The seals are particularly susceptible to degradation when the engine is frequently cold-started in New Zealand's varied climate and then allowed to idle without proper warm-up. Hardened seals allow engine oil to migrate down the intake valve stems into the combustion chamber, producing characteristic blue-grey smoke on cold starts that clears once the engine reaches operating temperature. Extended oil change intervals worsen the condition as degraded oil accelerates seal deterioration.

What you would notice

Blue-grey smoke from the exhaust on cold start that clears after a minute of running
Elevated engine oil consumption between service intervals
Fouled or oil-contaminated spark plugs on inspection
Occasional smoke puff when lifting off the throttle on the overrun after a long downhill

How to check it

Where to look. Intake and exhaust valve stem seals, both cylinder banks

Observe the exhaust pipe on a cold start after the engine has sat overnight. Blue or grey smoke that dissipates within 30 seconds to a minute is a strong indicator. Check the oil level and note the interval since the last service — high consumption (more than 500 ml per 2000 km) confirms active burning. Inspect spark plugs for oily carbon fouling on one or more cylinders.

What it costs to put right

$700 to $1,600 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.

Ask the seller

“Do you check the oil level between services, and how often do you need to top it up?”
“Has the car ever produced blue smoke on startup, especially on cold mornings?”

Now check the Subaru Impreza you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

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.

Subaru Impreza buyer questions

Is ej15 valve stem seal deterioration and oil burning serious on a Subaru Impreza?

We rate it major and common on the Subaru Impreza. The EJ15 1.5-litre boxer engine fitted to base-grade GD and GE/GH Imprezas develops oil burning as the rubber valve stem seals harden and shrink with age. The seals are particularly susceptible to degradation when the engine is frequently cold-started in New Zealand's varied climate and then allowed to idle without proper warm-up. Hardened seals allow engine oil to migrate down the intake valve stems into the combustion chamber, producing characteristic blue-grey smoke on cold starts that clears once the engine reaches operating temperature. Extended oil change intervals worsen the condition as degraded oil accelerates seal deterioration.

How much does it cost to fix on a Subaru Impreza?

$700 to $1,600 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Subaru Impreza years are affected?

Our research records this fault on the 2000–2011 Subaru Impreza. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.