Bruce In Philly

2009 C2S 90K miles

Question: Is it safe to DIY oil and filter changes? Particularly given the "need" for oil gauge re-calibration.

I just did another oil change and filter...7K miles, super minor black film on magnetic plug. Mobile 1.

My friend in Phoenix just had his dealer change his oil in his 2009 C2 and charged $230. DIY? I dunno, Walmart oil, Pelican filter... under $50.

Safe? This question is the result of posting by Macster about what goes on at a dealer oil change. (Marc, correct or add to what I write here.) He noted that dealers enter a VIN, based on that it will tell them how much to fill and that depends on which procedure they use: 1 hour drain or over night drain. They then "re-calibrate" the oil level metering system. I have also heard with my own ears, the service manager at my local dealership saying something like "you need the Porsche computer to do oil changes" (I can't believe I didn't ask him why... he was talking to another customer.)

I of course support DIY and just don't believe that DIYrs are putting their engines at risk. My supposition: Dealers have a detailed procedure because they use metered oil filling equipment (for expediency). They have to be accurate with the procedure or risk overfilling. DIY is different. My manual denoted 7.9 quarts with filter. I put in around 7 and a bit more, then drive around the block and then check and top off. This is a slower procedure which is why dealers can't do this.

Risk here is the meter re-calibration. First, I just can't believe the system Porsche put in there is so poor that it needs constant re-calibration. Second, my manual does not say I have to take it to the dealer for oil changes nor anything about this "required" re-calibration. Further, DIYrs measure the amount they put in so I can't imagine anyone putting in 10 quarts always waiting for the oil level display to come up to full. The manual has a very specific quantity specification... this is hard to screw up.

I and another Rennlister (can't remember who) posted on the PCA tech section this question on DIY oil change and the dealer's comments about needing the computer to do the oil change and noting re-calibration. They have not responded on the website Q&A.

Opinions?

Peace
Bruce in Philly

chuck911

My opinion, Porsche people tend to obsess and way over think these things. Way too much. Not knocking you, its more aimed at the ones who like you mentioned make comments that raise doubts sending people racing down rabbit holes. Or the guy (actually more than one) saying 5ml is a significant amount of oil to add. (For you metrically challenged mathlexics out there, think one teaspoon.) Its just nuts. Goes downhill faster for oil than anything else. Okay, maybe the need to "break-in".

When really, if you can follow some simple steps and pour back in approximately what you drained out, you can change your own oil. Don't over tighten. Don't leave a shop towel in there. You'll be fine.

Oil is kind of a big subject in most cars anyway. With the 911 though, I think maybe because oil was so crucial and heavily taxed due to being air-cooled for so long, that a huge cultural obsession developed among the 911 community. Pure conjecture. And anyone making money off anything is bound to mislead you as to difficulty and pitfalls, just so they can keep making money off you.

Don't get sucked into the FUDD. Embrace the ethos of the most successful slogan of all time: Just Do It!

Quadcammer

Agreed. Its a small motor with 9+ quarts in it. Even a half a quart makes no difference.

Just get it over with. Your car won't know the difference.

slicky rick

Is there such a procedure? Oil gauge recalibration?

shyamvenky

What do the shop manuals (Bentley??) say? If there is any special step, then those should also be mentioned.. correct?

phil996cab99

This is what is wrong with the business model. All makes.

For those of us who bought new, who did we buy from? PAG, PCNA, Dealer X?

Which entity has support responsibility? Which entity to engage detailed conversation re: how to take care of it (diy vs. not, repair authority, on and on), how to drive it (high 2nd vs. low 3rd, how hard, how often, downshift to 1st vs. not, lug vs. overrev, on and on), paint care, glass care, ...

We are forced to guess at such things. My guess is that PAG wants it pushed down to the dealership level. Problem with that is 3rd tier dealerships are much worse than top tier dealerships. The buying process never mentions PCNA, and that's not appropriate.

Cue the scavengers.

KNS

My BMW 128i has no dipstick either (maddening!). When I do an oil change I drain the oil into a large tub with half-quart markings up to ten quarts. If six and a half quarts drain out, six and a half quarts of new oil goes back in. Quick with no second guessing.

crossroads

Not sure about oil gauge recalibration but I'll probably go to the dealer for oil changes and other service while my car is still under CPO warranty. I may be a bit paranoid but that way they hopefully won't question any warranty work in the future. In my experience, going to the dealership once in while is good because my VIN can be checked for recalls and I get to know the service department. Most importantly, I get to know which technicians are good and those I should avoid.

I used to have a 993 and never took it to a dealership because I did all the service work myself. I sold it to my brother and he had to take it to a dealer because of crazy California smog testing. They found that there was a recall on a wiring harness that could catch fire and replaced it. So there is some benefit of having the dealer look at your car from time to time.

Macster

There is no calibration of the electronic oil level sensing system done, at least none I'm aware of.

Understand, I'm not against one changing the oil in his Porsche's engine. I'm only trying to impress upon everyone how things are different nowadays with these newer engines and the electronic oil level systems.

What is done -- and I believe this applies to other models though of course I have not had any reason to learn about this process for models other than those I own of have owned -- but what is done is the engine is brought to some specified minimum temperature (80C in the case of my 996 Turbo or hot enough to allow the electronic system to take a reading), the oil drained a specific amount of time (20 minutes but this is one hour for DFI engines), then based on the car's VIN a specific amount of oil is added back into the engine.

The oil level is checked and the electronic oil level reading is checked to confirm it reads what it should read.

Based on the info I have for my 2003 996 Turbo the above process requires the tech add in 7.8l of oil and upon checking the level the factory manual says the in-dash reading should be at the max line, not above or not below.

Now the above is what I was told but doesn't quite agree with what is in the factory manual I have for this car.

The exact wording is:

Slowly pour 7.8 litres of engine oil into the oil container.
Note
• Fill in engine oil slowly in order to allow the oil sufficient time to flow from the oil container into the crankcase.
8. Check the oil level. Check oil level on the instrument cluster and correct. Seven segments must be displayed in the instrument cluster.
Note
• This cannot be checked with the oil dipstick • The vehicle must stand horizontally
• The engine must be idling during the check.

Please note the "7.8 liters" mentioned above is also the volume mentioned when just changing the oil and not the filter too. The "real" amount comes from some internal Porsche database -- reading between the lines based on what I was told.

I have changed the oil in all of my Porsches at one time or another and I might resume doing this service again

When I changed the oil in my Boxster I had the dipstick to go by but I still counted the number of empty bottles of oil. And I took a reading using the electronic oil level system to confirm it agreed with the dipstick which agreed with the actual amount of oil I added to the engine. Might add here that at oil change time was the only time I used the dipstick. For checking the oil level at all other times I used the electronic oil level system.

When I changed the oil in my Cayman S of course I didn't have the dipstick available but counted the number of empty bottles of oil. Twice.

When I changed the oil in my 996 Turbo I didn't have a dipstick and couldn't even check the oil with the engine off so I counted the number of empty bottles of oil 3 times.

As best/accurately as I could I put in the amount of oil called for and then checked the electronic oil level readout was at least close to what it should read, without going over.

While it would appear "safe" to put in as much oil as one drained out if the electronic oil level system is acting up one may put back in too little or too much oil.

Just so it is clear one should put in a known quantity of oil, and the actual quantity of oil the engine should have, rather than rely upon the electronic oil level system for how much oil to put in.

(As I have mentioned before the oil dispensing gun in the service bay has a digital readout that shows to the 0.1 of a liter how much oil has been dispensed.)

The risk -- granted a small risk but with a big consequence -- is if the electronic oil level system is acting up you end up with too much oil or not enough oil in the engine.

One has to have 100% confidence in his oil change procedure that if the "indicated" oil level was way down (or way up) yet one knows the right amount of oil was put into the engine and then to know the problem is not with the amount of oil in the engine but with the electronic oil level system and to take steps to get this sorted out so to once again be able to with complete confidence rely upon this system to monitor the oil level in the engine after the oil change.

While I love the electronic oil level system and rely upon it to keep track of the oil level in the engine when it comes time to change the oil I count the number of empty bottles to know I have the right amount of oil in the engine and to confirm the electronic oil level system is operating correctly, reporting the oil level correctly.

Bruce In Philly

Good stuff, thanx.

I still want a da*n dipstick.

Peace
Bruce in Philly

KNS

If, by chance, you ever happen to have your engine rebuilt by Jake Raby, he can incorporate a dipstick into your M97.

Wayne Smith

The 9A1 motor has scavenging pumps in the pan to feed the internal sump chamber. The oil must weep back into the oil pan or you could not drain it. If the motor is off, where would you put the dipstick? To measure the oil, you have to know where it is. Motor on, scavenging pumps operating, time delay to stabilize oil in sump chamber, then measure ... electronically.

3Series

I change my own oil.

1.) I only change it myself when the weather is ideal, 65+ and sunny
2.) If it isn't ideal, I take it to the dealer or my indy
3.) I change the oil before track season maybe once during the season if I tracked 5-6 times already.
4.) I'll change it after track season

I have a DFI, I'll run the car to warm up the oil but will let it sit maybe 15min or so to gather my tools/supplies and let the oil cool a bit so I don't burn myself.

I'll let the car drain 30min to an hour, then I'll fill it back up 7-7.5 quarts. I'll aim low and fill it up over 2-3 days if it's still low. I'm not worried about getting every drop of oil out.

3Series

Interesting. I never knew why it took so long to read the oil level.