Hi All

I’ve got a 2011 Octavia mk2 1.4 tsi with an intermittent oil pressure warning light. I’ve replaced the oil pressure sensor, checked and topped up oil level and have fitted a new filter. Car was serviced 5500 miles ago.

The light doesn’t come on each time a drive but if it does it’s usually within 5 mins of starting a journey. I’m not sure if this engine has a pressure regulator as I can’t find it in the workshop manual I’ve been looking at. Can anyone advise if it does, where it is and whether this is my next thing to check/replace or should I focus on something else?

Thank you

How many miles has it covered?

About 110k

Might be the oil pump or perhaps oil pick up is partly blocked. Did it get the correct oil when last serviced? It may be that its too thick when cold or if the pickup is partly blocked not enough is getting through when cold . It might be worth getting oil pressure checked with a proper pressure guage.

Alasdair

Meant to add check the wiring from the pressure sensor back for continuity. It could be a broken wire/bad connection.

Alasdair

18 minutes ago, Alasdair1 said:

Might be the oil pump or perhaps oil pick up is partly blocked. Did it get the correct oil when last serviced? It may be that its too thick when cold or if the pickup is partly blocked not enough is getting through when cold . It might be worth getting oil pressure checked with a proper pressure guage.

Alasdair

Not sure what oil was used as i didn’t do it. I thought the pick up could be blocked but assumed it would be worse at high speed/higher temperatures as the oil demands would be higher but that doesn’t seem to be the case. Also the fact it’s only come on twice in the last 5 drives confuses me. I will check the wiring/connection, thanks for your help

I’d want to start by determining whether I’m chasing an instrumentation fault (the light telling lies) or a real problem. The only sure way to do this is to temporarily fit a mechanical gauge (into the hole where the switch normally goes) and measure the actual oil pressure.

If it’s a real problem then I’d be inclined to suspect a clogged oil pickup strainer because the oil will be thicker when cold.

However, I think it more likely it’s an instrumentation fault, and not necessarily the switch. I fought a similar issue on my son’s Arosa a few years ago. Checked the oil pressure with a mechanical gauge first, which was fine. Swapped the switch, which made no difference. Unfortunately VAG seem to have made it more complex than needed - there was quite a bit of electronics involved, none of which seemed to be broken, but it still turned the light on whenever it felt like it. Ignored it. After a while (months) it stopped doing it. Odd.

55 minutes ago, VitesseEFI said:

I’d want to start by determining whether I’m chasing an instrumentation fault (the light telling lies) or a real problem. The only sure way to do this is to temporarily fit a mechanical gauge (into the hole where the switch normally goes) and measure the actual oil pressure.

If it’s a real problem then I’d be inclined to suspect a clogged oil pickup strainer because the oil will be thicker when cold.

However, I think it more likely it’s an instrumentation fault, and not necessarily the switch. I fought a similar issue on my son’s Arosa a few years ago. Checked the oil pressure with a mechanical gauge first, which was fine. Swapped the switch, which made no difference. Unfortunately VAG seem to have made it more complex than needed - there was quite a bit of electronics involved, none of which seemed to be broken, but it still turned the light on whenever it felt like it. Ignored it. After a while (months) it stopped doing it. Odd.

Thanks for the advice. I’ve ordered a mechanical gauge so I can test what’s actually going on. With it being an intermittent issue I’ve leaning towards an electrical gremlin.

I’m assuming that if the oil pressure reads okay I can just ignore the light for the time being?

Just a though - my car handbook says if the warning flashes while driving, check the oil level and top up with oil as necessary.

Could it be a failing oil level sensor? If it has one?

No sure about very modern VAG cars but for at least 25 years, the oil pressure alarm isn't enabed until the engine revs are > than ~ 1600rpm, (previous to this there were 2 oil pressure switches fitted). If you have a genuine low oil pressure than it will cease to annunciate once the revs drop below this ~ 1600.

11 hours ago, pikpilot said:

Just a though - my car handbook says if the warning flashes while driving, check the oil level and top up with oil as necessary.

Could it be a failing oil level sensor? If it has one?

I’m pretty sure there’s a separate oil level warning light which I assume would come on if that sensor was failing?

2 hours ago, Johngerard said:

No sure about very modern VAG cars but for at least 25 years, the oil pressure alarm isn't enabed until the engine revs are > than ~ 1600rpm, (previous to this there were 2 oil pressure switches fitted). If you have a genuine low oil pressure than it will cease to annunciate once the revs drop below this ~ 1600.

Once the warning light is on and flashing it doesn’t go off until I switch the ignition off, regardless of the revs.

12 hours ago, Gasco said:

I’m pretty sure there’s a separate oil level warning light which I assume would come on if that sensor was failing?

It the same icon for both on my car.

On 21/01/2026 at 21:57, Gasco said:

The light doesn’t come on each time a drive but if it does it’s usually within 5 mins of starting a journey.

Under what conditions?

Idle, high or low rpm??

Does it extinguished when you rev it up a bit?

Sounds like low oil pressure, most likely to Manifest at LOW rpm where pump is spinning slower and oil is warm (thin).

Normally engines have great oil pressure when cold as the oil is thick

Id measure the pressure under a few conditions

On 22/01/2026 at 21:18, Gasco said:

it would be worse at high speed/higher temperatures

It would be worse a low speed high temp.

Oil pressure is higher at high speed, and higher with thicker(cold) oil

Yes, of course, the oil pressure is higher at higher revs, because of this due to higher specific power outputs the alarm has to be annunciated at a higher oil pressure and because of this and the (money saving) necessity of having to install two pressure switches then the "fix" was to disable the alarm until ~ 1600 RPM.

Edited 24 January24 Jan by Johngerard

On 23/01/2026 at 08:20, Johngerard said:

No sure about very modern VAG cars but for at least 25 years, the oil pressure alarm isn't enabed until the engine revs are > than ~ 1600rpm, (previous to this there were 2 oil pressure switches fitted). If you have a genuine low oil pressure than it will cease to annunciate once the revs drop below this ~ 1600.

That is this system which VAG refer to as “ dynamic oil pressure” (DOP) which does use two switches.

https://www.vwt4forum.co.uk/threads/flashing-oil-pressure-warning-problems.109439/

This is the system I was fighting in our old Arosa - not sure it’s valid for cars later than early 2000s, but I suspect there are still two switches.

The light coming on with 5 mins of a cold start is not because the oil is hot and thin. Possibly because it’s cold and thick and the gauze on the pump pick-up is sludgy - which is a known issue on some VAG engines. More likely instrumentation but needs verification as already discussed!

I’ve got a mechanical gauge and tested the pressure. It sits at about 20psi when idling (this is normal right?) but when the engine is revved the pressure drops. I assuming that means a blocked pick up is the likely culprit?

4 minutes ago, Gasco said:

I’ve got a mechanical gauge and tested the pressure. It sits at about 20psi when idling (this is normal right?) but when the engine is revved the pressure drops. I assuming that means a blocked pick up is the likely culprit?

Looks very like that IMO, what does the pressure fall to at say 1800/2000 RPM?

22 minutes ago, VitesseEFI said:

That is this system which VAG refer to as “ dynamic oil pressure” (DOP) which does use two switches.

https://www.vwt4forum.co.uk/threads/flashing-oil-pressure-warning-problems.109439/

This is the system I was fighting in our old Arosa - not sure it’s valid for cars later than early 2000s, but I suspect there are still two switches.

The light coming on with 5 mins of a cold start is not because the oil is hot and thin. Possibly because it’s cold and thick and the gauze on the pump pick-up is sludgy - which is a known issue on some VAG engines. More likely instrumentation but needs verification as already discussed!

I had a January 2000 Bora (manufactured in mid 1999) whic had one pressure switch + the inhibit up to ~ 1600 RPM.

4 minutes ago, Johngerard said:

Looks very like that IMO, what does the pressure fall to at say 1800/2000 RPM?

Doesn’t fall and stay at anything specific just flicks around between approx 10-20 range

17 minutes ago, Gasco said:

Doesn’t fall and stay at anything specific just flicks around between approx 10-20 range

That's a very low oil pressure, don't know what it should be in the mid/high rpm range but would expect at least 50/60 psi, needs investigating.

Does sound like the pick-up strainer/gauze could be partially blocked. The erratic readings at higher rpm imply pump cavitation. Needs urgent investigation.