SDI Engine: High Oil Consumption Causes

Hello!

I'm experiencing a slow but significant problem: the oil consumption of my SDI engine (Seat Ibiza 1.9L SDI, AQM 50kW/68hp, year 2000, mileage 67,000 km) is increasing excessively.
Initially, I was only using 0.5 liters of oil per 1000 km, but now the oil consumption has increased to 1.5 liters per 1000 km. However, I'm not losing any oil; it's being burned. I've already tried different oils and viscosities, but the consumption hasn't decreased.
'Does anyone else have experience with a similar problem? The workshops haven't encountered this issue before (and there's nothing about it in the service manual). The engine (oil scraper ring) shouldn't have any problems at this mileage, nor should the valve stem seals, or...? By the way, the error memory is clear.'

Thank you for your help and your tips in advance. Maxx

I don't have any oil loss, which means the oil is being burned along with the fuel.

How do you confirm this observation? The oil consumption is so high that it almost suggests a leak, because otherwise the engine would hardly run properly. Is your rear clean, or can you visibly see smoke coming from the engine in the rearview mirror? What do the glow plugs look like?

However, I don't have any oil loss, which means the oil is being burned along with the fuel.

How do you confirm this view? The oil consumption is so high that one almost has to suspect a leak, because otherwise the engine would hardly run properly. Is your rear clean, or does the engine also visibly smoke in the rearview mirror? What do the glow plugs look like?

'Sorry, I forgot to mention that I work for ARBÖ, which is like your ADAC, as a technician (VW-Audi apprenticeship). I have prior experience. If the engine were leaking oil, it would be covered in oil by now, but it's completely dry and dusty. When the engine is cold, it produces a relatively large amount of smoke when idling, which I can see in my rearview mirror when I'm stopped. The engine runs normally, because the oil consumption, converted, is 'only' 0.15 liters per 100 km, which isn't really noticeable in normal driving.'
I haven't checked the glow plugs yet, as the car starts normally (even without preheating) at 0 degrees Celsius.
Maxx.

Worn valve stem seals are less likely to occur with high mileage. However, it is possible that piston rings have broken off and are stuck in the cylinders, preventing the oil scraper rings from functioning properly.


It's just a guess... Just do a compression test.

Best regards!

Worn valve stem seals are less likely at higher mileage. However, it is possible that piston ring(s) have broken off and that the oil scraper rings are no longer performing their intended function correctly.


It's just a guess... Just do a compression test.

Hi!

Hello!
Thank you for your email. The compression is 100% okay - thankfully.

Okay, then you can only proceed step by step. First, check the valve stem seals. If there's no improvement, then you can remove the pistons and replace the oil scraper rings. That's a very straightforward task.

Best regards!

I just realized that, since the car isn't that old, I would argue for a goodwill arrangement if the maintenance intervals have been followed.

Since VW only offers a warranty for 3 years or up to 100,000 km, the issue must be reported to the authorized VW workshop. They will then decide on a case-by-case basis whether to approve the repair, even if the warranty or goodwill period has expired.

You will naturally have to decide whether repairing it yourself or taking it to a mechanic is cheaper than having it fixed under a warranty or goodwill arrangement.


Best regards!