Engine Oil

[fruitsalad]

Why is my Vauxhall using so much engine oil it's not leaking underneath, and there's no smoke coming from the car.

[EDDIE51]

How much is it using? It is normal to use some oil.

[fruitsalad]

Every couple of weeks I seem to be putting some in when I check it which is every 2 or 3 weeks it's very very low on the dip stick

[EDDIE51]

Top it up to the top mark on the dip stick, then after 2 weeks or whatever top it up again but keep a note of how much it needs. If it is not smoking or leaking it can't be a major problem. How old is the car? Some cars just do use a bit of oil. Also make a note of the mileage when you top up. A car uses more oil the more miles it does, time alone is not much of an indication of oil use.

[MantaRay]

How much are you putting in at a time? e.g. 0.25 litre?, 2 litres?

[TWR]

1 / Worn Engine
( Has this been Checked?)
2 / Oil Leak
Has this been checked? Compression Tested?
If the Engine Breather is blocked the oil will find a way to release due to internal pressure, this may be the front lower cam Shaft oil Seal which is below the bottom pulley, another area is the rear Oil seal that is between the gearbox & the engine, this seal can not be seen as it's within the bellhousing, I have just replaced the Sump seal on my BMW E46 that did not show sign of oil loss even though the Sump Shield were removed. the first job is to get the underside power washed, if there is a undertray on the car, this has to be removed then check that area.

[tonyav]

If it's not leaking oil it's gotta be burning it.
If your Vauxhall has a petrol 16 valve ecotec engine my guess is that the valve stem seals have hardened and their letting oil into the combustion chambers.
Catalytic converters can mask blue smoke.

[Hopkirk]

I can confirm what Tony is saying.

I have an Astra with a 1.6 16v Ecotec engine, and since about 100,000 miles it has drunk oil big time.
When I googled for an explanation I found that these engines are notorious for it.

On the plus side I don't change the oil so often, as it constantly gets fresh oil added.

[Hopkirk]

Tony, will it eventually knacker my catalytic converter?