ga993

Okay, rookie here. I just realized that these cars consume oil (2 quarts per 600 miles per my mechanic) and that you need to top them off from time to time. I feaked and thought I had a leak, until my wrench calmed me down. I had my oil changed a couple of months ago, so wasn't even thinking about it, until I noticed my oil level guage was near the red. One qt of Mobil 1 15w-50 and the guage came back up to mid level. Boy, do I feel like a goof.

goofballdeluxe

Most people here will tell you that 2 quarts per 600 miles is waaaay too much oil consumption. One quart every 800 miles means you're due for a top-end rebuild.

matt777

At some point in time your plugs will foul and the exhaust will be blue. At one quart/300 miles you would have to be there. I'm guessing that the consumption isn't that bad. You have to check the oil with the engine properly warmed and the car on level ground using the dipstick. If you keep the level over half way on the dip stick you may well cause increased consumption. Before getting too worried I would track consumption using this method. The level gauge is not very useful. It it doesn't register at all (after idling for a minute or 2) when the engine is fully warmed I might check the oil.

grwoolf

I had this problem. When I first got the car, I tried to keep the oil near the top of the dipstick. The car was going through oil pretty quick. After reading about this issue on rennlist, I keep the oil level under the half way point and the usage dropped significantly. At half way up the dipstick, my oil level guage just barely registers anything, so it always looks low on the guage unless I take the level up near the top of the dipstick. I plan to try to adjust the sending unit during my next oil change if it's not too hard.

ga993

I mentioned to my mechanic that I was suspect of the level guage. He told me he totally trusts it. Not sure who to believe, as I have heard that several times on this forum. As for the dipstick, please tell me where the oil should be reading. My stick has the twisted metal at the tip. Where should it read?

95C4VanIsle

I agree with the poster above, that is way too much oil consumption. I add about one half of a litre of oil for every 3,000 miles. But, do as Matt says and follow consumption closely. The oil should be no further than half way up the twisted section.

RallyJon

There's a place in between Porsche's "we don't want to have to fix your engine" acceptable amount of oil consumption, the independent shop's "we DO want to fix your engine, come right in and bring your firstborn!" acceptable amount of oil consumption, and the "mine burns xxx so if yours burns more that's too much" Rennlist version.

Clean plugs? Good power? No smoke except on startup? Then why worry?

ga993

Thanks, that leads to a new question. What happens if the oil reads at the top of the twisted section? I have too much oil?

BSL

For reference, on my '95 with 95k miles, I drove from central Florida to Chicago, IL putting about 1,500 miles on the car and the oil level hasn't shown a noticeable change.

CADguy

I agree with both Matt and Grant above. When I first bought my 993 (about a year ago), I would keep adding oil to keep the level at the top of the dip stick twisty section. I read here not to do this, and now keep it at the middle (or slightly less) of the twisty section.
Also, the oil level gauge is just an indicator, not the ultimate truth (that would be the dip stick). Here in Colorado, when it is cooler (maybe below 70 deg), the oil level gauge never leaves the red, even after a spirited romp, fully warmed up and on a level surface idling for 30 sec to a minute.
Kind of sounds like you might need to consider getting a new mechanic

Good luck

Black993

Sounds like you may want to source out a new mechanic
Even the owners manual says it may not be entirely accurate....

Half way up the dipstick is good. Don't rely on the gauge. 2qts in 600 miles is WAY too much consumption!

CADguy

Not necessarily, but don't put any more oil in!
If you have overfilled it, I hear that it will be obvious

Let the oil level drop down to about the middle of the twisted section, note the miles, then keep an eye on it from there.

mongrelcat

I did a bunch of reading on this a few days ago after the oil volume gauge stopped registering yet the dipstick range was still fine. I discovered:

-Each car is different, and has it's own "sweet spot" that Matt and others have alluded to previously

-The dipstick range shows ~1.8qts, the volume gauge shows ~1qt

-The sender unit can be adjusted so that the gauge is more accurate for your particular car and operating environment (good pics of the assemblies are here, just search, look for a threads/posts by "shamrock")

-Do not overfill. If anything underfill slightly until you understand your car (by experimentation, observation and documentation)

-Per the manual if you do a lot of short trips and then suddenly do a long highway trip (or track day!) your consumption will *seem* to go up measurably due to diluting ingredients evaporating out of the oil

-It's A LOT easier to read the dipstick 2-3000 miles after an oil change. New oil w/ the 993 dipstick is a tough read. Daylight helps, but it's quite tricky. Look for a little bit of bubbling to indicate the actual level. Marking the dipstick with gradations using a triangle file has helped some with this too. Others blot the dipstick with a layer of paper towel to better *see* the level, etc. Or you can just wipe/pull/wipe/pull the dipstick a bunch of times until you're sure. (lol)

Check the oil level (by gauge or dipstick) only after the car is sufficiently warm (20-30 minutes of driving) and only on level ground and only after idling for 3 minutes or more.

With my car after about 3 minutes of idling (after being sufficiently warmed up, first,) at the current oil level I see the temp gauge at operating temp (8:00 o'clock) and the volume gauge pretty much mirrors it at ~4:00 o'clock. On the dipstick this registers at about 2/3rds.

(You will know the car is at operating temp when you see the temp gauge hit the 8:00 o'clock mark and then drop a bit as the high speed fan kicks in for the first time of that drive. In my case right now the weather is about 45* or so, and when the fan kicks in the temp gauge immediately drops 2-3 needle widths, actually below the operating temp mark for a bit.)

I let the car idle for 15+ minutes (after being sufficiently warmed up, first,) just to test. The temp gauge went to ~9:30, the highest I have yet seen it under any conditions. (I had never seen it above 9:00 prior to this.) At that point the volume gauge mirrored this at ~2:30. On the dipstick this registers at 4/5ths to 5/6ths.

As temps go up, so does volume. This direct correlation between temp and volume is shown by the two gauge needles mirroring each other.

I think that at this level I am above my car's sweet spot, and expect it to drop down a bit and settle there (hopefully!) The factory says something like 1qt / 600 miles is in spec. My mechanic told me 1qt / 3-400 miles is fine. Hopefully, I'm no where near that consumption level, but I'm still getting to know the car and not sure yet. Some of the other signs to look for to see if you're consuming oil: smoke at startup, smoke after letting off in 2nd gear from redline, smoke during shifts. I have none of these symptoms at 102k miles, and no top-end job yet. YMMV, literally.

At 12+ qts oil capacity and three gauges, with all the attending eccentricities, these cars certainly are unique beasts.

There are literally dozens of threads on this general topic, but that's the jist of what I've learned. I'm just going by memory, so some of the above may be a bit fuzzy, hope it helps though. Search the 993 subforum with "oil" in the subject line and read the threads with the most replies to learn all you ever wanted to know about the lifeblood of your 993......

Bearclaw

I have two-cycle motors that I don't put that much oil in.
I have 3500 miles on this oil change, and it's still near the top-level mark.
On a normal car, I'd say maybe coolant was getting into the crankcase and raising the level - but I don't think that's the case in my Porsche!

Oil consumption varies all over the place with these engines, I think that's why the acceptable parameters got to be so wide. But you're using way too much oil. Forget smoke or power - doesn't it **** you off to keep having to add that much oil all the time?

csertich

If your mechanic is totally trusting of the gauge and NOT reading your dipstick, go somewhere else.

I pretend I don't have the gauge and just check the oil like I've always done. The dipstick.
After an oil change, to check the oil, I use a piece of paper towel and run it down the stick until I see some soak into the paper. Otherwise, I have a hard time seeing the oil level.
I keep the level in the middle of the swirls on the dipstick.

Good luck.

chuck