Very odd behaviour after going above 3.5k-4k rpm (2.0 TFSI)

[JetSetter1984]

Hello, just joined and posted a pic of my car and would appreciate any input on the subject.

I can drive the car day and night normally and no warnings/lights ever trigger, it drives lovely and sounds very smooth.

I do, however, experience something odd sometimes, not everytime, about 30-40% of the time.

If I go above somewhere around 3500-4000rpm with the accelerator pressed, the car pulls like a train and shows no warnings, but when I return to idle, I get a low oil pressure warning.

With the warning on the car still sounds and drives the same, smooth sounding with no strange noises from the engine.

It only ever happens after a bit of hard acceleration and returning to idle, never while driving normally or idling after driving normally, and switching the car off for a minute and back on normally clears it until I accelerate hard again.

The only strange noise from the car is always there regardless, and is a whine that increases/decreases with rpm and it happens both when driving and in neutral.

Car has had both oil pressure sensors recently replaced, new oil pump, and an oil change using valvoline 5w30 and bosch filter. I have also just ordered a new low oil pressure sensor from febi bilstein, as I have heard sometimes the sensors tolerances can be out if they are not from a good source, and I have no idea where the mechanic ordered the last set from. I will be fitting that within the next few days.

Any help/advice/clues on what it could be will be greatly appreciated, cheers!

[cliffcoggin]

Daren.

You seem to have covered the obvious causes of low oil pressure. I think it is significant that the low pressure only happens after hard acceleration when the oil would get hotter than normal, so I wonder if there is a restriction in the oil cooler, assuming you have one.

[JetSetter1984]

Thank you so much for the response. Very good advice. I have not thought about the oil cooler. Is it something that is easy to remove and clean or replace? Or a complete pain and expensive like the oil pump?

[cliffcoggin]

I can't help on that score with any certainty. It might be a separate heat exchanger mounted behind the main radiator, or it might be integrated into the radiator. Let's hope somebody more knowledgeable will chip in.

[JetSetter1984]

Once again, many thanks for taking the time and effort to help. I will contact a mechanic later and hopefully get some insight on this. Hopefully it's not too big a job but definitely could potentially be the cause.

[cliffcoggin]

Please let us know the outcome.

[JetSetter1984]

On 4/23/2025 at 4:15 PM, cliffcoggin said:

Please let us know the outcome.

Thank you so much for the suggestion. The oil cooler turned up (ordered from Autodoc for £38 with gasket) and was fitted a few days ago. The oil cooler gasket was also replaced and the oil filter housing gasket was wrecked and botched with silicone before. This was also replaced. Also a new brown low oil pressure sensor from febi bilstein at the same time, to replace the official Audi one, although the last one was changed recently too, thought I may aswell do that. Had a few spirited drives to try get the warning up again, but nothing so far! I'm going to mark this as a solution for now and if it somehow happens again, I will update this thread. As things stand the oil cooler and gaskets seem to have done the trick. My greatest appreciation to Cliff for this suggestion, thank you so much. I'd love to buy you a drink sir!