Hello My name isXXXXX will be glad to assist you today in answering your questions.
What year is your a4, and what engine do you have in it.
All the oil pumps in those cars were junk, 2.0 diesel in the Passat was the worse, there is a upgraded oil pump design you can have installed that solves the problem, but its expensive and not worth the investement.
2.0 L TDI,
Year 2008 (58 plate)
I have heard through my friend who had the issue that a garage does their own version for about £300 but I don't know how much it would then cost to fit, due to labour costs?
Does it affect all of them eventually or might I get lucky and not have any problems?
Also, what will happen if I am driving and it loses the oil - will I just slow down or come to a sudden halt? My friend was lucky because it happened during a service in his local garage!
If the engine loses oil pressure, it will suffer catastrophic damage, the engine will destroy its self. You will slow down, but you will hear a lot noise and the engine will loose power. Loosing oil pressure is worse than having a timing belt or chain break. Loss of oil pressure makes every component suspect and in need of inspection and possible replacement
The engine your referring to is a flip of a coin some run great and never see a issue, others fail before 100,000 km. It seems to effect most of them, and normal service or lack there of does not seem to effect the problem. The issue is the pump itself, VW came out with a updated pump for the 2005 Passat TDI in the states to fix this issue, but it has crept back in to the market with the newer cars.
The pump in my opinion is undersized, and any stress on it causes it to fail. I would be careful with that engine, regular oil changes, and if needed engine oil flushes as needed. Also make sure oil level is full at all times. The pumps I have seen appear they have destroyed themselves. Its really difficult to find a point of failure when all you have is chewed up metal, but internal blockage is what most guys tell me.
Thanks, XXXXX XXXXX sense. I presume this is only a diesel problem, not their petrol engines that were optional at the time?
The petrol engines did have oil pump issues but it was usually caused by lack of vehicle service. If oil changes were done on time the petrol engines did not have the same problems as the diesel. But without records most the time its hard to prove a person did oil changes.
And even in some cases when oil changes were done the engine still had sludging problems. that required new oil pump breather system, turbo charger,
Now the 2liter engine petrol was good but the lower end was weak and after about 80,000km the rings were bad or needed replaced.