BobbyB

After my last oil change, my oil gauge stayed near the top when on a level surface and the car at operating temperature. When the gauge started to read in the middle as in your photo, I was also in the middle of the dip stick, about 1/2 quart down.

993inNC

Thats exactly what I get, mid gauge, mid stick. Monique, I'm not convinced that there is anything wrong with our level gauges in general. Keep in mind most Porsche owners use their cars infrequently and don't get used to what they are seeing. Driving often and in all types of cituations allows one to witness the reactions of the gauge at all times, study what happens when and why. In doing that it has been very easy to conclude when to look at it and what its telling me.

Just my .02 cents........I guess one must do what feels best

Monique

I don't disagree with your statement but if you are uncertain about its behavior, the only absolutely reliable information comes from the dipstick.

When Steve Weiner wakes up on the "best" coast, he'll state as I do!

amfp

I don't rely on guage either. When engine hot, let idle on level ground for about minute and than check dipstick. The top line does not mean full, it means max level of oil. I keep my oil level between the min and max level on the stick. Think all 911 owners had the overfill experience.

Monique

Actually, Steve told me to say this!

JasonAndreas

I think a big problem is that people don't pay attention to their oil temperature gauge. Without first knowing what the oil temperature is, your oil level reading is almost completely useless. If your oil level gauge (or dipstick) is showing a full tank but the oil temperature is below 194F you will be in for a big surprise if the oil temperature starts shooting up much. As the temperature rises the oil expands. You just have to learn to ignore your oil level gauge while driving around (unless it is always reading completely full). The only way to get a true reading (from the gauge or dipstick) is with the car at idle and with oil temperature at/around 194F. Remember that it is almost impossible to underfill a 993, at 800rpm there is no problem having only 6 quarts in the whole system. So its not an issue if you think you might be 1/2 quart low.

At one time I was also one of the non-believers then I spent way too much time inside the oil tank and noticed the dipstick is situated about 2 inches to the left of the oil level float. I haven't looked at the dipstick since.

coltj

Another voice for relying on the dipstick; I use the level gage only as a rough indicator. In fact, I believe my level gage reads LOW based on the dipstick readings. Haven't bothered to get it calibrated/recalibrated abd don't intend to spend the $$ to do so. I check the level each time before I shut the car down, as long as it's on a level surface.

Using a data logger, I find it takes at least 12-15 minutes(city/suburb roads) to get the oil up to steady-state temperature(~250-260F).

STLPCA

Monique is dead on. The best level indicator is the dipstick. If your gauge happens to agree w/your dipstick (as does mine) great, but many don't. Overfilling is worse than underfilling by a quart. In fact, many here run at the mid or bottom of the dipstick/gauge especially for hard use.

JD83

Another vote for the dip stick for me.
I check it when the car is fully warm on a level surface
such as my garage or at a gas station where the concrete slabs around the
pumps are pretty level.

My guess is that the poll will be way in favor of the stick!

Greg Bell

Another can of worms opened.... You'll get different views from many people but they all come down to two basic points of view, namely the dipstick or the gauge. Work out what's best for you. After calibrating my dipstick with the gauge I can say with confidence (for my car) that it the temp has hit the first mark, the ground is level, the engine has been allowed to idle for several minutes and the oil level is in or near the red at the bottom one litre will bring the level back up somewhere near the top. It's not rocket science, just get to know the idiosyncracies of your car.

rkass

Notwithstanding Monique's point which is absolutely on target, I just had oil changed and Chris's observation is on point with my guage. Full Oil, guage at top of mark. I seem to recall in my other 993 that if guage got below halfway this was an indicator to check to oil using the dipstick as Monique and others point out. To be safe, use of stick should be weekly (some say daily) task. Hope this helps.

JasonAndreas

If your steady-state oil temperature is ~250F-260F there might be a problem with your cooling system, the thermostat might not be opening, etc. If everything is working properly you should have a steady-state oil temp ~50F cooler.

FisterD

Another question....
How many quarts do you put in for an oil change?
I use between 10-11 qts. This brings the level up right between the low & high markson the dipstick. My gauge usually reads in the red, so I don't bother with it.
Do some of you guys actually put in 12 full quarts?

coltj

Jason,

Thanks for the reply.

I consistently see steady temperatures in the 240-255F range both on my '96 C4 and my friend's '96 TT in city/street driving, not highway cruising. I think I can see evidence that the thermostat is opening both in the temp gage and in the data stream.

Anyone have data on oil operating temp?

Monique

Coltj,

There is a good writeup on www.p-car.com in the DIY. Explains the operating characteristics rather well.