Low oil pressure S4 b8.5

[cmdv]

Just had a service, oil and filter replaced.
Day later I get a "low oil pressure" warning which went away about 5 seconds later. (I heard the beep but didn't actually see the fault). So day after that I drive it for 10 mins and the warning comes on and I see that it's "low oil pressure". I stop the car thinking the worse.

Come back couple of hours later turn it on and nothing, drive home and when I pull up at home it comes on again!!

Instantly I'm thinking the sensor must be playing up, so I think I'll do a manual oil pressure test see the actual pressure. Removed the sensor (proper hard sensor to get to!!!).
On first engine start it read 1.5bar which is within the specs (minimum 1.2 at idle and minimum 1.5 bar 2000 rpm).
Rev to 2k and it pops up a little to just under 2 bar. I'm thinking happy days it's a faulty sensor.

So I turn off the engine and try doing the same test and it's now dropped down to 1.2bar at iddle and 1.7 at 2k.
To make sure, I turn off engine again and give it another shot and this time it's dropped to just bellow 1bar idle and 1.5 at 2k

Try one last time and the warning light comes on again

This take the sensor out of the equasion, what else should I be looking at?
I'm really hoping it's not the oil pump as that will probably be a right **** to replace I would imagine

 

[PenttisHSR]

First off - what oil was used and have you checked the level ?

 

[cmdv]

It was 5W 40, which is right spec but after taking it back to the garage that did the service and it turns out it's a part / o ring inside the oil filter housing!! (I can't quite see what it could be from the exploded view but guess it sits at the bottom somewhere)

So happy it was something so simple really thought after checking the oil pressure sensor that it was going to be a rocky road to the bottom of my wallet!!
But couple of quid and wait for back order part and will be back in action

 

[ninjag]

Could it be this inner seal "A"? There seems to be a few variants for the 3.0 though.

I'm sure mine is more like this, where I can only see one seal which comes with the filter:

 

[cmdv]

@ninjag I'm not too sure I didn't even open the oil filter housing just went straight for the oil pressure sensor (which was a mistake given what a pain it is to get to haha).

But will report back when I find out what it is, I'll try get part number as they had to order it from Audi (which makes me think it wouldn't be just the 3 from the last exploded view as those must be common as muck).

 

[rum4mo]

For your and your engine's sake, I'd be buying a new oil filter and fitting it complete with all its supplied seals.

In my experience of trying to order in something like a seal that gets supplied with a new filter, the fact that it is "back order" means that no one has ever asked for one, so you will probably have changed cars before that "back order" seal comes into stock.

ECP for instance sell the MANN equivalent oil filter for not much money - and the original VW Group branded oil filter will also have MANN branding printed on it.

In my case it was a petrol fuel filter seal on a 2002 VW Polo, and the reason that I needed to buy one was down to ignorance, the new fuel pressure regulator came with one - 10 years on I'm well past giving up any hope of that "back ordered" seal ever turning up, paid for but never supplied, any way that car was sold on and seems to have died a few years after it was sold on.

Edit:- I've always preferred 5W-30 oil for my B8 S4.

 

[PenttisHSR]

The filter comes with new seals included as stated above.
Here is the correct filter for your car - MANN OE Boxed with seals and fitting instructions.

Mann Hummel OE Quality Replacement Engine Oil Filter HU 7029 z | eBay

Part Number: HU 7029 z. Mann Oil Filter. The oil circuit is of central importance here, as only clean engine oil can permanently ensure consistent engine performance. Bypass valve: ensures that oil is available when the engine is cold started or when the service interval has been significantly...

www.ebay.co.uk

 

[ninjag]

The filter comes with new seals included as stated above.
Here is the correct filter for your car - MANN OE Boxed with seals and fitting instructions.

Mann Hummel OE Quality Replacement Engine Oil Filter HU 7029 z | eBay

Part Number: HU 7029 z. Mann Oil Filter. The oil circuit is of central importance here, as only clean engine oil can permanently ensure consistent engine performance. Bypass valve: ensures that oil is available when the engine is cold started or when the service interval has been significantly...

www.ebay.co.uk

The height is showing 155mm?

The filter for my B8.5 is only 105mm - you've got me worried now! lol

Here's the one I bought for mine: https://www.eurocarparts.com/p/mann-filter-oil-filter-501440669

I looked up the parts diagrams and got this part number (06E115562B) which returns 105mm height filters?

 

[PenttisHSR]

@ninjag you are correct!
In your pictures above, the top two are from a B8 and the lower one is from a B8.5 - very different seals.
I do apologise, I am mistaken, the CAKA & CREC engines have diferent oil filters!
In my defence the mann catalogue lists both engines, however when you go further it splits them.
I have a B8
@cmdv - The correct Mann Filter for B8.5 is HU 7035Y - and it will come with a new seal

Please see attached, and Thanks - learn something every day!

 

[cmdv]

Thanks @ninjag I spoke to my garage again and it's actually the oil bypass/drain valve that sits inside the oil filter housing (lower half)
So it's not the filter and seal that sits between top and bottom. The filter is brand new and the right part number, they are VAG registered so get all the same oils etc from the Audi specs.

Just came to light as new filter was fitted when doing the oil change and it must have disturbed something, apparently it's noted in the audi system as a common fault. (How true that is I'm unsure) But the people at the garage are currently having to store 19 cars waiting for parts on back oder even paying extra giving it a OR (car Off Road or something like that) label.

Sucks because it's such a simple part, I even asked if we can just purchase the whole filter housing thinking that it would maybe be more available but no luck. Just have to go with put my car until it comes in

Better than risking my engine though, rather go without for a little bit that go through that pain. Can imagine how much a new engine would cost and the labour!!!!

 

[ninjag]

I wasn't 100% sure but thanks for clarifying. PenttisHSR, Audi part numbers seem to be a bit of a nightmare with all sorts of revisions. Spent ages trying to verify the correct part numbers for the front suspension and even ended up mistorquing a ball joint as it was the upgraded M14.

Thanks for the extra info cmdv, I'll need to bear that in mind when doing oil changes.

 

[cmdv]

So after waiting 3 weeks for a part to come in, this was the old broken one. It sat at the bottom of the oil filter housing and the rubber bit is what snapped off the circular bit to the right of it. It was hard to the touch not very rubbery anymore!!

And apparently there was a notice of this failing part in the system, worth investigating incase you get told to replace oil pump as that's a right job!!

 

[CM02]

2012 B8 S4 with 118,000 miles.
I am having a similar issue. I did a good bit of maintenance work which included replacing the oil filter housing/adapter due to a leak. I installed a Vaico unit that I bought from FCP Euro. A few hundred miles after doing the maintenance I started getting the low oil pressure warning at idle when the engine was hot. I tested the oil pressure manually and it is definitely low.
15 psi at idle, 20 psi at 2k rpm, and 20 psi at 3k rpm (measured with engine cold). Would this flapper cause this issue? I took a photo of the flapper in the Vaico oil filter adapter I installed. It looks very different from the photo in the above post.
Thanks for any feedback. Hoping this could be a simple fix.

 

[PenttisHSR]

@CM02 As above B8 CAKA & B8.5 CREC have different oil filters

 

[CM02]

Solved my issue. It was the same flapper/anti-return valve issue:

P164D - Low Oil Pressure - Gas in Oil

Need help from the gurus out there⦠2012 S4 with 118,00 miles. Stage 2 single pulley. A few weeks ago I replaced the water pump, thermostat and PCV chasing a coolant leak causing coolant to pool in the valley of the engine. While everything was torn apart also did carbon cleaning, valve...

www.audizine.com