turbodogs02

The manual is vague, only stating 3.5 bar and above is normal. Ever since my autocross last week, my oil pressure has generally been pegged at 5 bar. Occasionally it will float back down between 3.5 and 4 but under normal driving it will immediately head right back up to 5 and stay there. Any thoughts or concerns with this? Bueller? It has normally been in the "normal" range (3.5 or better) but never consistently pegged at 5 before.

TheBruce

I would recommend checking your oil filter and removing the oil pan to check for any debris stuck in the oil pickup. I had something similar happen after my first AutoX. About a week later I found a few large metal shavings in my oil filter. Scared the crap out of me. Jake from Flat6 was able to immediately identify them as drillings from the original machining of the oil galleries. He explained bits like that sometimes don't get washed out properly during manufacturing and you will see them in the filter during break-in. The theory was the prior owner just hadn't driven the car very hard and my first AutoX knocked them out 10 years later...

Luckily the oil filter did its job and I found no additional debris in the oil pan. The filter has been spotless for 30k miles since then.

Keep us posted. I think I have a writeup on removing the oil pan and happy to walk you through it. Its a pretty easy job.

nosnow

The oil pressure senders are a failure point. On a cold engine with the key in accessory mode is there any oil pressure registered? It should be zero, if not zero you probably have a bad pressure sensor. Google it and you will find lots of details.

TheBruce

This is good advice and an easy first step to check. However the symptoms starting after an AutoX makes me think this should be investigated further.

swingwing

Seems to me that a restricted oil pickup would result in low oil pressure, not high as OP's seeing. Way more hazardous than high pressure methinks. I think he's got a oil pressure sensor issue. I rarely see oil pressure above 3 bar on my '09 3.6L.

TheBruce

@swingwing you are probably right. But from my experience, I saw abnormally high oil pressure on my drive home from the AutoX like the OP and then found the debris in the oil filter a few days later. My assumption is if debris is knocked loose in the oil galleries you could see an increase in pressure depending on where the restriction occurs in relation to the sensor. Spitballing here but that was the best theory I had for my situation...

turbodogs02

Awesome information everyone, thanks! The Bruce, you described perfectly my exact circumstances and I would be inclined to follow your remedy suggestion. I am not necessarily equipped with "tools" but I am willing to learn and in fact, want to get more involved with some basic home maintenance for education and cost savings!

I checked oil levels during the event and discovered I was one segment below the full reading. After I got home, I rechecked, had the same reading, and added the appropriate amount of oil to bring it back to the full level.

During driving, like today for example, when letting off the accelerator into my parking lot at work, the gauge dropped from 5 down to around 3.5ish, floated up to 4 on throttle and then again back up to 5 where it has been when back on the gas.

G.I.G.

FYI, I believe we are supposed to aim for the middle (between the two arrows) when topping off our oil. From my understanding, you do not want to overfill these engines. On my first oil change, I started by adding 7.5L of oil (on the low side). Then when I went to top it off, I overshot a little and ended up at the top bar between the arrows. That's still acceptable, but you don't want to go over that.

Regarding the oil pressure, my 997.1 C2S exhibits the same oil pressure readings you've been having lately. I asked my contact at my indy who used to work for Porsche in Atlanta and was there during the development of the 9A1, and knows a ton about the M96/M97 as well. He said these oil pressures are perfectly normal, so I wouldn't stress out about it too much.

turbodogs02

For sure, I'm always extra cautious when adding oil....to the point of going just under what would be recommended, and then checking levels again. That's good to hear about the pressures being relatively normal....I think I'll definitely look to do an oil change at the minimum (road trips and more AX coming soon), and see what that yields.

G.I.G.

Well, I'll be. I just went out and checked my car after reading this (it's been sitting since yesterday afternoon), and it was showing 1 1/2 bar on the oil pressure gauge with the engine off. Looks like I'll be having to address that sooner than later.

G.I.G.

After reading through this again and seeing my oil pressure gauge at 1 1/2 bar with the engine off and sitting overnight, I decided to call my indy again to ask about it. He said it is not uncommon for a car to show residual oil pressure even after sitting overnight or longer.

He also said that this time of year (it's still pretty cool here in CO, even on the warmer days we've had here over the last couple of weeks) that even when the engine is warmed up, that the outside air temp will keep the oil a little thicker, and therefore not dropping in pressure in the system below 3 or 4 bar, even at idle. He said I have nothing to worry about.

@turbodogs02 based on what I just learned, maybe your oil pressure was lower when you were running it hard at your autocross event due to the oil temp. Maybe it is showing higher pressure due to lower temps as has been the case with my car too.

Just out of curiosity, what oil brand and viscosity are you running?

turbodogs02

I did it (thanks for the tip, btw), and pressure was zero as it should be, so pressure sensor would probably check out. I have an oil change scheduled for Thursday, so we'll see what that yields.

turbodogs02

When I started the AX day, oil pressures were reading what had been "normal" range to date, 3.5 and above but not pegged at 5. During the course of the day, I noticed it had pegged at 5 and it has more or less remained there since (minus slight fluctuations). The car had an oil change on 2/4/19 at 43,410 mi. and the car is at 44,711 mi. now. Our air temps have been all over, so I'm not sure it'd be related to that. As for brand of oil, that's a really good question and one that I'm going to ask my indy when I go in on Thursday....viscosity is 5/40.

bgoetz

Mine is mostly at 5 when under load. When not under load it drops to around 3, it always has been this way since I have owned it with zero issues. In fact I think I read this is normal for our cars.

G.I.G.

OK, good to know. Keep us posted, but I think you're cool. I'm running 5W-40 myself.

Yeah, from talking to my indy and doing some more research, it sounds like higher oil pressure isn't unusual depending on the circumstances (oil viscosity, oil temp, outside temp, etc.). I don't believe the oil pump, even with some sort of blockage, could produce enough oil pressure to damage the engine.

When you need to worry, is if the oil pressure is too low or zero....