74goldtarga

I did my second oil change recently. The first one went perfectly / flawlessly. The most recent change I overfilled, which is weird to me as I followed the same protocol as the first one - the only difference is that the first time I removed the plug from the bottom front of the block and also from the tank and the second time my wife picked up a new filter and crush washer from the dealer when she was there and they only sent home the washer for the plug at the front center part of the block. I drained all the oil that would come out in an hour of sitting open and replaced about 7L - not sure how much less I drained (if any but my subsequent experience suggests it was a meaningful amount). Car ran fine and I could not, at the time, figure out how to get a reading, there was no smoking or dash warnings so I figured wrongly that I was okay.

I go to the track having driven around a bunch without ever getting a reading from the car on the oil level - as I am going onto the track I get an "oil level too high to drive on warning". I pull off and ask a Porsche Certified Technician what I should do and he says to drain some oil, about 250cc - also tells me the best way to get the car to give a reading is to just let it idle. I jack up the car and loosen the plug, which is pretty damned hot, and try to carefully drain hot oil into a one quart bottle so that I can see how much I have drained - this is messy and nearly impossible trackside with jackstands. I have the clever idea of using a long hex wrench to hold the plug so that i don't burn my fingers - of course I end up dropping the plug and getting hot oil all over everything including my forearms and bravely/stupidly get the plug back in before the engine is drained. I get the pan back on the car (a leap of faith) and measure the oil - I get a green reading one notch below the yellow mark. I drive the car and again get an oil level too high warning - which seems impossible given how much hot oil I seemed to spill (obviously not measured). So I loosen the oil filter using an oil filter tool (one of the cheap black plastic ones) and a crescent wrench - this is a MUCH better way to allow oil to drain for the following reasons:

1. It actually drains at a reasonable speed well before you are at risk of having it come off completely and lose control of the situation
2. Using the oil filter tool the heat is manageable
3. You aren't re-torquing the crush washer which is probably against the rules.

I finally get the oil level correct (I think) or at least for now the readout is green and I have no warnings. I must say I do not trust this system - I am nervous that I could damage the engine with either a too-high or too low level, that would be a really stupid way to damage an expensive engine. If you could get it to give you a level accurately and quickly that would be nice (how about a volume number accurate to 100cc or something - too late for a ten year old car i realizer but anyway). A genius idea would be a metal probe that you could dip into the engine and it would tell you the level. Other lessons for me - the technician says they use 6L as the amount they replace in this car which is good to know and is obviously less than I replaced.

I am wondering if there is a good graduated jug that anyone uses to more accurately measure the amount of oil they remove when doing a change so the amount to replace is more obvious?

WHAT IS THE QUICKEST WAY / SEQUENCE TO GET THE CAR TO GIVE YOU A READING? - right now my procedure is raise the trunklid, open the oil filler cap, wait a minute, replace the cap and close the trunklid, start the car and allow to idle on a level surface, go to the oil level screen - this sequence will give me a reading after the car idles (even starting out warm) after 10-15 minutes which is totally ridiculous.

Related question, what is the quickest way to get the TPMS to read - I have given up on using the circuit setting as the car always wants to start-over and re-initialize the TPMS and then I am stuck without seeing pressures for an indeterminate length of time (hours / days).

Thanks to anyone who can help me be less stupid.

dbv1

Plug in PIWIS or iCarsoft or whatever, go to DME->View Data->Oil Pressure Control->O110 Engine oil level sensor. My cooled off 991.2 reads 25.18 mm right now.

Does that help?

I'm not sure how useful the reading will be on a cold engine given they're dry sump. I would take a reading before dumping the oil as a reference. Run the engine for 30 sec after the initial oil fill just to fill the filter and all the nooks and crannies and then take a reading.

I haven't used this reading on previous oil changes but I'll check it this time.

74goldtarga

Yeah, didn’t know that was possible, great suggestion. Thanks

johnsopa

For future reference to drain a little bit at a time loosen the oil filter, let it drain, retighten.

I hate these electronic level measurements.

KOAN

I have successfully removed a small amount of oil (200 cc) with a 60 cc syringe and vinyl tubing through the filling hole. No spill at all, took about 30 secs. Car can be hot or cold, and not on a lift.

johnsopa

I've done the same, just make 100% sure you use high temp tubing and that it's long enough that if you somehow lose hold of the top end, it's not going to drop down into the fill tube.

Captain Scurry

My protocol:
1. check the oil level before draining
2. use cheap, large measuring cups to measure amount of oil drained
3. Replace exact same amount, maybe a touch more depending on pre-drain level.
4. As most know, oil level sensor is way to sensitive, easy to overfill, so it only takes a small amount of oil to go from low to high.
5. Level seems good (upper green) but then you typically gets mild overfill warning after driving (especially on track). Pop trunk, open oil fill cap, close both, usually solves problem until a bit of oil burned off.

991carreradriver

My advice is - don't overthink it. I have done at least 20 oil changes on my car and always do the same thing. I let it drain from the drain plug and oil filter for 30 minutes and then fill with 7qts. I always wind up with two bars below top after the sensor provides readings.