Originally Posted by Ahsai

Drive the car hot and leave the car parked overnight and check the stick before firing the engine in the morning. This is the proper way to get a consistent and accurate reading, period.

Originally Posted by 911Syncro

I have the opposite problem: the oil level doesn't go down. A 2002, so its the 3.6 engine, 80K miles, have it for a little over 3 months now and put on about 2,500 miles. The oil level is still at the full marker on the dipstick, same as it initially was, and little darker than the original golden color.

I guess that is good news, but thanks very much to everyone who wrote about how the sensor works, and general level oil behavior -- I have more to learn.

Originally Posted by Turbojamie

So rather than waiting the 10 seconds for the oil level monitor to report you simply ignored it for x amount of time and it was a full 4 low? Kind of irresponsible if you ask me. Hopefully nothing was damaged by the excessively low oil level. The engine will consume "some" oil but they are all over the place as far as how much. For instance my 03 C4S would use 1/2 quart in 5,000 km of driving at the most.

Originally Posted by DBJoe996

Good idea on voodoo! Now for the issue. You are doing the right thing. You need to establish a baseline for oil consumption versus mileage. Remember the sump/engine contains about 10 QT's of oil. Check your oil level on the dipstick when the engine is stone cold, meaning, like in the morning before you fire it up. Then do this consistently for several days. Fill it back up to full if it drops and note your mileage. That should give you some good baseline data for oil consumption versus mileage.

Depending on the weather temps where you are, going to a 5W could help. You do not want to even begin to think about why the engine consumes to much oil - scored bores, piston rings, valve stems and seats, and so on. What you want to do right now is see how much oil is consumed and whether that is within a tolerable range.

Also note that I said to use the dipstick. The oil level guage is not that accurate, readings can vary depending on a lot of different factors. Use the dipstick for accuracy.

The oil pressure sounds about right, however, the oil pressure sender unit in our cars are notorious for erroneous readings, especially when old. Might consider replacing it.

Originally Posted by Macster

It is possible to burn 4 quarts of oil in ~300 miles but I would have to believe you would notice the engine smoking. Occassionally I observe a vehicle taking off from a stop light, or just going down the road/freeway and oil smoke trailing behind the vehicle. While it is clear the engine is burning oil I strongly suspect it is not burning 4 quarts in 300 miles.

Right now you do not know for sure just how much oil is in the engine.

My recommendation would be to have the engine oil properly drained and refilled with a known and correct quantity of oil appropriate for your car and at this time the tech would then check the electronic oil level sensor and system is working properly. Ask him to confirm the oil dipstick also reads correctly.

You want to know the engine has the right amount of oil and that both the electronic and dipstick measurement systems are reporting oil levels that are in agreement with each other and just as important in agreement with how much oil is actually in the engine.

Then drive the car as you normally do and keep track of the oil level.

Be very consistent in when and how you check this. The car wants to be very level. A bit up or down at either end can affect my Boxster's oil level reading by 2 bars. With the car tilted sideways the level varies even more.

I check my Boxster's oil both dead cold -- with the car having sat overnight unused -- and fully up to temperature. Often this oil level check is made when I stop and fill up the gas tank. The engine is hot, fully warmed up, and the gas station drive is quite level. After filling the tank the oil level reading count down starts at 5 seconds.

Check the oil level and monitor the change in the level. If you see the level dropping as you add miles then there's something going on. There's not much you can do on your driveway. I'd not bother trying a different oil. Really if the engine is using oil at the rate you suspect (but which I doubt is actually occurring) no oil will help and you don't want to run the wrong oil and possibly damange the engine internals when the heavy oil consumption might not be that serious of a problem, though obviously its cause should be found and fixed ASAP.

If you see the level varying -- this is assuming you use the electronic oil level system -- then what is probably going on is the electronic oil level sensor has suffered a problem (a loop of wire is loose and moves about and this affects oil level reading) -- and this needs to be addressed. Probably by having the oil level sensor replaced.

Originally Posted by DASC4S

That isn't what I said. I normally don't wait the 45 seconds for the oil level indicator on the dash, because it's 45 seconds on my car. I do check the dipstick. I was merely using that the description of actually waiting for the indicator to display as a lead in to me seeing the low oil and prompting another check of the dipstick. It was not that low the full 4 weeks. Thanks for your editorial opinion about my behavior and actual facts about your oil consumption, since this is a technical forum and not glamour magazine after all.

Originally Posted by DASC4S

DBJoe996, thanks. I ordered an LN engineering magnetic oil plug and an oil filter tool to get ready for a change. Looks like I will be changing out the oil a little sooner than planned. I hope to maybe do it tomorrow. I plan on draining and measuring what I get, then filling and checking vs mileage. I don't mind a little oil burn, but if I'm right about how it consumed in a week I may need to invest in Exxon-Mobil. Prior to this I had a Subaru Impreza with a flat-4 boxer engine, which consumed about a quart every 5k mileage, so I'm used to this being normal.

Sadly, I need to need to wrap up some work on an 86 vette (new radiator and spark plugs) that is occupying my garage. My driveway is sloped, way to much to consider jacking on it.

I've seen some of the threads on the oil pressure sender unit, that's unfortunate. I mainly rely on the dipstick, because I am us not patient enough to sit for the f average o45 seconds for the computer to read it. One thing that I am wondering is if I actually have the right one. It's probably unlikely but I've heard it happening where previous owners for some reason put a different one in and then who knows what you are measuring it isn't the right length. I'll see if I can get a picture today and if members can confirm I've got the right one.

Originally Posted by DBJoe996

Sounds like a good plan! Especially the magnetic drain plug. Another good thing is to change to the LN Oil Filter adapter with a normal type spin on oil filter w/no bypass.

I have noticed that my oil level guage starts measuring as soon as I turn the ignition to ON, before starting. It reads in about 10 seconds. However, if you do the same thing just after filling up with gas, it says it will take like 20-40 minutes on the countdown clock. I never wait for that one, just fire and move on. Strange behavior indeed.

I know it will take some time to check the oil consumption versus mileage. Interested in hearing what you find out.

Originally Posted by DBJoe996

Sounds like a good plan! Especially the magnetic drain plug. Another good thing is to change to the LN Oil Filter adapter with a normal type spin on oil filter w/no bypass.

I have noticed that my oil level guage starts measuring as soon as I turn the ignition to ON, before starting. It reads in about 10 seconds. However, if you do the same thing just after filling up with gas, it says it will take like 20-40 minutes on the countdown clock. I never wait for that one, just fire and move on. Strange behavior indeed.

I know it will take some time to check the oil consumption versus mileage. Interested in hearing what you find out.

Originally Posted by Volkert

Confused on your 45 seconds to measure oil level.. Mine does it in 5 seconds? My routine is to get into the car, switch on ignition, then close door and put safety belt. By then it has read the oil level and I start. I have a C2 Mk.1.

Originally Posted by murphyslaw1978

Same here. But I have the same car, mk1. I have seen a 45-second timer before, but I don't really want to wait for that one. I think that timer is after an engine re-start while hot. If it's an engine re-start while cold, the timer countdown can be really high, many minutes long - I think I've seen as high as 59 minutes. I trust none of these except for the one that the manual indicates is proper: 5-second cold start after sitting a long time, and the hot refuel re-start.

Im glad our cars have dipsticks

Originally Posted by DASC4S

DBJoe996, thanks. I ordered an LN engineering magnetic oil plug and an oil filter tool to get ready for a change. Looks like I will be changing out the oil a little sooner than planned. I hope to maybe do it tomorrow. I plan on draining and measuring what I get, then filling and checking vs mileage. I don't mind a little oil burn, but if I'm right about how it consumed in a week I may need to invest in Exxon-Mobil. Prior to this I had a Subaru Impreza with a flat-4 boxer engine, which consumed about a quart every 5k mileage, so I'm used to this being normal.

Sadly, I need to need to wrap up some work on an 86 vette (new radiator and spark plugs) that is occupying my garage. My driveway is sloped, way to much to consider jacking on it.

I've seen some of the threads on the oil pressure sender unit, that's unfortunate. I mainly rely on the dipstick, because I am us not patient enough to sit for the f average o45 seconds for the computer to read it. One thing that I am wondering is if I actually have the right one. It's probably unlikely but I've heard it happening where previous owners for some reason put a different one in and then who knows what you are measuring it isn't the right length. I'll see if I can get a picture today and if members can confirm I've got the right one.