chancecasey

I just checked my oil at 5,000 miles since the P.O. had his dealer change it.

All bars are lit up, including the one OVER the full mark.

Does this pretty much guarantee the P.O.'s dealer overfilled it? I mean, it's had 5,000 miles to burn some oil off.

Car was just warmed up for this purpose, was sitting in my garage which I am pretty sure is level.

Would this explain the oily, sooty, black film that collects at the rear of the car, and around the side vents, after a few hours of driving?

eddielasvegas

Well, I would follow the oil level check procedure exactly in your manual and recheck. I think it has to be at normal operating temp versus warmed up. Check it multiple times to see if you get a consistent reading.

If it still shows overfilled, I would change the oil myself (since the oil has 5,000 miles on it) and be mindful of how much oil is added after the first 7-ish quarts. After the first seven qts, I add oil in 10 oz. fills and recheck with the last fill or two using 5 oz. fills, knowing mine takes ~8 qts. I also drain mine for at least 12 hours so I know about as much of the oil is out as possible.

Bit of a pain to say the least and it makes me long for a good oil fashioned dipstick, but ensures no chance of overfill.

Good luck,

Eddie

DBH

I will assume you're driving a late model Cayman/Boxter without a dipstick. The "electronic" dipstick very finicky. After 5k miles, I think you would have burned off some oil. Probably enough to bring it down one notch? Anyway, follow the directions in the manual to get a (sort of) true reading. I usually find that if you open the hatch (or trunk on the Boxter) before starting the car, then driving for a while, until the oil level registers, you'll get a good reading.


Soot on or near the tail pipes is not unusual particularly if you have PSE. Soot around the side vents (behind the doors) would have nothing to do with engine oil level.

Macster

What was the oil level cold (or hot?) right after the oil change?

With my Boxster I can check the oil level cold and I check the level just to make sure the engine has oil in it and the level is good.

With my Turbo I can't check the oil level cold and often when I pick up the car the car is cold -- been sitting hours since the engine was last started/run -- but I give the car a shakedown drive and as soon as the oil is hot enough check the level.

If you use the car for short trips what can happen is the oil never gets very hot and the water that it collects -- due to combustion blow-by and is normal -- can increase the volume of the oil. Don't laugh. Way back in the winter of 2002 shortly after I bought my 2002 Boxster I had the oil analyzed -- at 4K miles -- and the analysis found there was around 7% water in the oil. With approx. 9 quarts of oil that works out to around 0.6qt of water.

If you want get the oil analyzed and see if it has a big load of water. Or just have the oil/filter service done -- I have been doing 5K mile oil/filter services for my Bxoster (and Turbo) ever since I bought the car(s) -- and be sure to confirm the oil level is ok *before* you drive 5K miles...

Soot around the exhaust outlets is normal. Like I like to say: Soot happens. For every gallon of gasoline the engine produces around 19lbs of carbon. Most is in the form of CO2 but some will be in the form of soot.

At the side vents that's probably not from your car but from the stuff that is in the air. My Turbo gets a bit of grunge on the leading edges of the side intercooler air intakes. Your Cayman is collecting a bit of grunge. Grunge happens.

chancecasey

Thanks, guys! Yes, sorry, don't know how to set my signature - I have a 2011 Cayman S now at 55,000. I followed the directions to a "T", checked multiple times/locations all had "overfull" reading when very warm and flat/level on all of them. I had not considered it gaining volume over time in moisture, etc., that is interesting. It is usually DRIVEN and for extended periods of time, not just to the corner store and back.

Update - today got the oil changed, noted my concern on fill level, and it came back 1 notch under the full mark which I am happy with. It reads that way consistently under same warm testing conditions as before with the overfill indication.

Great indy shop here in town did it for $130 including resetting the computer and uses LiquiMoly 5w 40 (Austin TX). I am curious to learn to do it myself also, haven't looked up how to do that yet. OTOH, it's hard to beat $35 of labor if you don't have a lift at home...

Macster

These cars/engines are cold blooded. You live in a generally mild climate but similar to the one I "enjoyed" when I lived just east of KC Mo. While the temperatures were not often real hot (at least not in the high 90's/low 100's) the humidity was high and I used the A/C almost all the time. I joked there were about 2 weeks in spring and 2 weeks in fall when I could drive with the A/C off and not be too hot/damp or too cold.

The problem with the A/C is the radiator fans run all the time and this works to keep the engine cooler than it would be otherwise.

And even in winter when it was too cold to run the A/C (the compressor doesn't run if the outside temperature is too low to prevent the evaporator from icing up) even my lowly 2002 Boxster would run cool even when driving around 60 miles at 70mph freeway speeds.

It takes some "special" driving (puttering around town driving in stop/go and go mode rather than blasting WOT down the freeway or a deserted back road and with the A/C *off*) and weather conditions -- warm but not so warm as to require one run the A/C to keep from melting -- to get the coolant temperature hot enough (my observation is 212F) to cause the radiator fans to come on. At 212F one expects the oil is at least this hot and this then helps boil any water out of the oil. But this process can only forestall the inevitable. To ensure all the water is removed from the engine oil the oil must be drained and replaced periodically.

Hopefully that "1 notch under the full mark" was obtained by the tech draining the oil properly (the DFI engines have a 1 hour drain time IIRC) and then adding the correct amount of oil back into the engine.

Changing the oil in these cars is not hard. Did both my Boxster, my 2008 Cayman S, and my Turbo myself using just a set of Rhino Ramps and backing the car onto the ramps to provide me enough room to work under the car.

The car being out of level doesn't appear to affect the amount of oil that is drained out. Having the engine up to temperature and letting the oil drain the proper time is critical.

I would then button up the engine, and after cleaning the oil filter housing -- I had two and alternated between them -- putting on new o-rings and installing a new filter element, and using fresh oil to fill the housing (except the Turbo: the housing goes in upside down so the oil would pour out) -- dumping in nearly the right amount of oil. After checking for any leaks, and counting the empty oil bottles 3 times, I'd start the engine and after a bit of delay just in case I'd drive the car off the ramps and let the engine idle a while until the Turbo oil was hot enough to check the level or the Boxster/Cayman engine was back up to temperature.

For the Turbo I'd check the oil level and if a bit low -- which I expected -- I'd add more to bring the level up to the max line.

For the Boxster/Cayman I'd let the car sit with the engine off a while -- while I gathered up my tools and put things away -- then check the oil level and if a bit low -- again which I expected -- I'd add more to bring the level up to the max line.

But during the initial refill I'd be sure I added close to -- but still under -- the amount of oil required to ensure that the digital oil level sensor/system read close to the max line but still under and was therefore trustworthy.

When adding a bit of oil to bring the level up I'd keep track of how much oil I added. I'd note how far down the level was and then add the amount of oil that should have the level at the max line. It never happened to me but you have to be aware that if say the level is down one bar and this works out to say a quarter of a quart if you add that much oil and the level is still down or the level is too high that's a sign the oil level sensor may be acting up.

What you want to avoid is say the engine requires 8.25 quarts of oil and putting in say just 8 quarts and finding the oil level reads high and removing oil over and over again until you have removed too much and with the level still showing high not knowing just how much oil is really in the engine any more.

Or removing some oil only to find then the level is reading low and dealing with the confusion this brings. (If the sensor is bad the reading can vary due to at least one failure mode the sensor can experience.)

Or you find the level showing low and add in oil and yet the level still shows low then after a round or two of this you give up and just decide to leave it be and run the engine probably considerably overfilled with oil.

Really I can't stress how important it is to use the oil change to verify the electronic/digital oil level sensor system is working properly and can be depended upon/relied upon to keep track of the engine oil level all the way to the next oil change interval.