[SOLVED] Low oil pressure at idle

[OllieVRS]

EDIT 23/05/2023: The low oil pressure light I got in this post was likely just from hard cornering with a below average oil level while on track. By pure coincidence I later discover there is actually something mechanical causing insufficient oil pressure, but only at idle RPMs.



^new suspension setup, H&R 45-50mm Ultra Lows on OEM shocks, wheels are 18" Bola B1s

Planning on doing my first track day ever in the Octy.

It's only a half day on the track so two and a half hours, and I'm not planning on pushing her too hard as I've no experience of driving on a track other than go karting.

I'll change the oil before hand, is it necessary to change it after too? The Millers CFS 5W40 NT+ is €81 for 5L so don't want to throw that money down the drain 

Current setup, appreciate any and all feedback on this  :

Brakes are all pretty much factory and had all pads and discs replaced 10k kilometers ago. They're still squeaky as a barstewards though, and of the rear calipers leave more brake dust that the other 3, but isn't seized or anything like that. Also brake fluid was inspected by the garage then and deemed to be fine.

Suspension is now on lowering springs and OEM shocks with new top mounts, and all the bushings are in decent condition. I'll get an alignment before the track day too.

Tyres are Eagle F1 Asym 6s, and only have a few thousand kms on them.

Engine's got a RamAir standard size CAI and is running a 95RON-tuned remap, and oil pump still has an active balance shaft. Rev G DV.

As for octane booster, on UK track days you guys are obviously running 99, but are you running any octane booster on top of that?

Cheers!

[gj124]

Don't overthink it, no need to change oil afterwards. Recently serviced with decent tyres and new brakes is a good start Maybe take it easy as it's your first time and come in after a few laps to let the brakes and tyres cool down. If anything fails, just upgrade it for next time!

[Clarkj93]

Not familiar with the circuits in IE but do some research of general flow and lines before hand if possible via YouTube and preferably from experienced drivers during races etc.

Your oil is good mate, that's what I use too. I change it every 2 FULL track days which some would consider very often so you're good.

Remember no road without extensive modification is well suited to the track so you'll notice some weaknesses:
- The good year tyres will roll over the sidewall a little due to the sidewall being soft for road use and the stock camber being low with soft rubber bushes.
- The suspension will feel soft and produce a lot of roll
- The brakes will overheat if pushed for too long.

None of these are big issues to worry about except the brakes, some race fluid would be ideal and keeping stints to under 15 minutes a time and you'll be OK.

No not really seen many people use octane boosters really.

[OllieVRS]

Cheers for the replies and advice lads 

Also as for 'circuits' in IE, the depressing reality is that it's just 'circuit'. In the Republic of Ireland the literally one race track, Mondello Park.

I'll ask for maximum front negative camber when I get my alignment done as there's still 5mm of tyre poke on the new springs, so that should help reduce sidewall roll on the Good Years.

As for racing brake fluid, I'll look into getting it changed, just need to find a garage that is willing to source it and fit it for me as I'm not too comfortable with changing such a safety-critical component myself with no experience of working on brakes.

What would happen if I stuck to OEM brake fluid and it overheated, would there be a dramatic explosion under the bonnet or would the brake pedal just go soft?

The planned track day is on Easter Monday, so I've got plenty of time to prepare in advance, so further advice is still appreciated 

Thanks!

[Clarkj93]

Oh that's annoying. I thought you guys would have more than just 1.

The camber won't be adjustable unless you have adjustable top mounts/adjustable ball joints/adjustable bushes etc. But if the car is lower it may give you a little extra neg camber anyway.

Ate's race fluid is cheap and decent. Think Murray motorsport is a motorsport retailer in Republic of Ireland? They'll have a range of race fluids, just pick something that has a boiling point of at least 280 degrees Celsius dry.

You can use oem yes, it has a low boiling point so when it hits that the fluid develops air bubbles which means you may develop a dead spot/spongy pedal. The race fluid stuff will have a "wet" rating too which means once its been boiled it can still withstand X temperature which is another advantage over em stuff.

Personally I would change the fluid and keep stints to under 15 mins and you'll have a worry free day.

Tyres are a real contributor to brake temps too, so your road tyres shouldn't push them beyond the limit with short stints. If you went for a stickier tyre you ought to look at some better pads/cooling.

[OllieVRS]

Here's the brake fluid that came out of the car, the mechanic that did it is shocked that my previous garage said last year that the brake fluid was still fine when checked by their machine.

From the limited service history on the car, it seems like the brake fluid was last changed in 2013, or 60k miles ago 

Replaced with Millers Motorsport Racing Brake Fluid 300 PLUS. Took 1.2 litres. Haven't had a chance to test the brakes yet, but at least I know the fluid won't get me killed now 

Cheers

[Clarkj93]

Engine oil ? Nice choice in fluid.

[OllieVRS]

Trackday complete, and car has survived without any major problems (or so I think?).

But I got low oil pressure on a hard corner towards the end of it. As soon as I came out of the corner the light disappeared. So I assumed right away this was due to oil starvation, but it made little sense considering the oil was at 70% when cold between min and max three days before.

Coming back to the pit slowly revealed the dipstick to be at 60%, on a hot engine.

I changed the oil a couple days ago, completed a 550km round trip to Portrush in NI yesterday (mostly sitting around 3.5k revs), and then did 18 rounds of Mondello Park's 2.8km track today.

Would it make sense that it used so much oil in so little distance, considering how hard it's been driven? I would've expected Miller's expensive nanostuff to have protected it a bit better than this. There are no visible oil leaks.

Cheers

[Clarkj93]

Hope you enjoyed!

You should not see low oil pressure on road tyres, these engines are pretty good when it comes to oil distribution on cornering, would only worry about it on slick tyres of very sticky semi slicks.

Do you know the condition of your oil pickup pipe? They can clog up a little and cause issues, not that common but well documented issue that can happen. Simple cleaning sorts them out. But mainly I would make sure the oil is always at max before going on track which is possibly your issue. You should not be using that much of the Millers stuff really, you may have a leak somewhere.

I had an oil leak through the rocker cover gasket which was small enough to not leave any oil puddles but enough over time that I would have to occasionally top up. Since I sorted that out and using Miller's oil I've not seen any oil usage at all that is visible on the dip stick, doesn't do many miles but most of its miles are very hard.

[OllieVRS]

I did enjoy the track day, thanks! It's just that little scare at the end that got me.

I had a whole saga on this forum over the span of 4 months back in 2021 about low oil pressure, but back then it was due to the oil being over filled/pick up clogged, I never found out the true cause. This was from dodgy maintenance by the previous owner, and I got the light literally the next day after buying it off them (doing some hard acceleration, but the light only popped up when slowly driving around an estate at low RPM, and then later again slowing for a red light after hard acceleration) , and unfortunately it was a private sale so there was no going back.

The oil had metal shavings in it. After replacing the pick-up, pump chain cover and even the big end bearings on the rods, the issue disappeared and the oil pressure tested fine, measuring within spec using a proper oil pressure gauge. Each subsequent time I changed the oil afterwards there were less and less shavings, so the issue should have been sorted. Engine compression was fine too. The last oil change I did had no visible metal, even a holding a magnet to the used oil pouring out of the sump didn't affect it, unlike with initial oil changes.

On the track today it happened at at least 3k RPM around a sharp bend, a completely different scenario to last time. The measurement of the oil after I took afterwards was on a hot engine, I've not checked the cold level but I bet it's much lower than the 60% on the dipstick I measured.

It's also worth noting my oil level sensor may be broken, a Mechanic's Delphi scan once showed a 00562, oil sensor 'short circuit to positive or open circuit' 'intermittent'. And I've never gotten a low oil light, even despite my oil once going below min.

I choose to believe it's the oil level and sharp bend that caused it, because I can't fathom digging around in the guts of the engine again for months trying to find the cause   

[OllieVRS]

Morning update: Bad news, the oil level only dropped 150ml over the course of the track day. There's not even the tiniest puddle of oil under the car, which I was praying for.

The oil pressure light happened on long right turn, exactly at the moment I started turning in harder during the turn. But @Clarkj93 said these engines are pretty good with oil distribution so, I have no idea what could have caused an oil pressure light at that high of RPM. There was no rattling or burning smell, the latter of which happened last time I got the light.

The car is just lowered on H&R springs on OEM shocks and Eagle F1 Asymmetric 6s, so hardly slicks.

Guess it's time to drop the sump then? Or just buy an oil pressure gauge and stick it in? The old one I used was crap, so I'll buy a new one.

[OllieVRS]

For reference, this is roughly where on the track around where  happened. Unfortunately we didn't get a video of the lap when the light happened, this is taken from another video. I think the light happened as I upshifted to fourth. Lasted for 3 seconds and disappeared. Never reappeared. In my memory the turn was much tighter than it was in reality, so I don't think oil starvation from hard cornering was the cause.



Maybe I'll just drain the oil, inspect it for anything suspicious, have a gander around through the sump plug hole with an endoscope, check the filter for metal shavings, and if nothing's there I'll put in the new oil and see if it comes back.

[ROH ECHT]

Morning update: Bad news, the oil level only dropped 150ml over the course of the track day. There's not even the tiniest puddle of oil under the car, which I was praying for.

In case you aren't aware of this; all of the modern engine oils are tested, and known to lose anywhere between 5% and 13% from evaporation alone, caused by heat. The evaporation can occur rather quickly, especially if the oil reaches a high temp...and the duration of heat exposure is another 'evap' factor.

[pudding]

Your car has history with the oil light coming on, so could be related.  Maybe pushing it on track has uncovered a weakness in the oil system?

I'm amazed more GTIs don't throw the pressure warning light on track to be honest as they don't even have baffled sumps! 

Either way, unless the pressure sensor is knackered, you've lost pressure, so a bearing/journal or two could have suffered.  Look for metal shavings or glitter in your next oil change.

Maybe try a 10W60 if consumption is an issue on track.  30 and 40 will burn off super fast.

[OllieVRS]

Apologies for the spew of posts above, I'm just going crazy overthinking everything at this point, and I can't drain the oil right because the weather's horrendous here.

Morning update: Bad news, the oil level only dropped 150ml over the course of the track day. There's not even the tiniest puddle of oil under the car, which I was praying for.

In case you aren't aware of this; all of the modern engine oils are tested, and known to lose anywhere between 5% and 13% from evaporation alone, caused by heat. The evaporation can occur rather quickly, especially if the oil reaches a high temp...and the duration of heat exposure is another 'evap' factor.

Wow that's more than I expected. But I meant the other way around. I meant I was hoping it had burnt more oil as that would've meant the light was caused by oil starvation from low oil, the simplest fix. In this situation i would've preferred to find the dipstick on min.

Your car has history with the oil light coming on, so could be related.  Maybe pushing it on track has uncovered a weakness in the oil system?

I'm amazed more GTIs don't throw the pressure warning light on track to be honest as they don't even have baffled sumps! 

Either way, unless the pressure sensor is knackered, you've lost pressure, so a bearing/journal or two could have suffered.  Look for metal shavings or glitter in your next oil change.

Maybe try a 10W60 if consumption is an issue on track.  30 and 40 will burn off super fast.

It could possibly be so that something internal has finally given way, but I doubt it considering the engine sounds perfectly normal, and there's no smell like the last time.

Since our engines don't have baffled sumps, do you think there's a possibility it could have been momentary oil starvation caused by a long and tight 100kmh bend? My friend in the passenger seat who was there when the light happened said it was my fastest speed through that bend. And this was after two previous hot laps.

Since the light disappeared once the revs dropped below ~2.5k (which would mean less oil pressure), I am becoming fairly certain it was caused by temporary starvation or something temporarily blocked the pick up pipe.

But I appreciate the replies as always. Hopefully this isn't the start of the end