Petza914

I send all my oil samples to Blackstone for every oil change on every vehicle, including my boat. I also have them run the TAN & TBN analysis.

Are you going to do a leakdown test next? Did you find much oil in the Driver's side intercooler?

NelaK

Leakdown test passed. Also don't appear to be leaks in the coolant system.

For the intercooler piping - where is it and how do I get access to it? I've been Googling it and everyone refers to it as an 'obvious' thing and I can't find any clear videos/pictures. I must have missed it in the Intro to Cayenne's class :P.

Dilberto

Intercooler plumbing is below the vehicle. You need to remove the belly pan to access the pressure piping and hoses directly from Turbo hot side inlet, going to intercooler.

Petza914

The intercoolers are the things next to the center radiator that air flows into through the big side bumper openings. The plumbing into them is accessible from the sides and down low once the fender liners are removed.

nodoors

Part number #30 or #27 on this diagram depending on if you have a 957 or 958...

NelaK

Thanks for the info guys.

The car is still at the shop the warranty people recommended. Its waiting for them to get a chance to check the intercooler piping.

As a partial update though - I extracted an oil sample. At first I thought it was full of metal particles but after a few minutes they revealed themselves to be bubbles and the engine oil looked perfect ... Anyways - the sample is off to Blackstone... I paid UPS a pretty penny to get it to Blackstone by 10:30am next day so hopefully I'll hear back quickly.

NelaK

After a bunch of delays with UPS, I finally got my lab results. It seems the lab results are good news and nothing seems out of the ordinary? I'm not 100% on the metal of the various components but my understanding is that the Cayenne has an aluminum block with a nikasil coating, the pistons are aluminum and the piston rings are cast iron? The aluminum, nickle and iron numbers all seem reasonable (as I understand them). Silicon seems high but I'm inclined to think that its just contamination from when I was extracting the sample. It was a really windy day with lots of dirt blowing around. I've also seen oil analysis reports with silicon levels that are way higher and that was considered acceptable. The fuel also makes sense since I wasn't really able to get the engine fully warmed up before taking the sample.

Petza914

Blackstone is great for the quantitative analysis part (I use them too), but their conclusions are always a little too "rose colored glasses" for me. No way I'd run that oil with those results any further, and they say to go another 2,000 miles. I would change to a different oil. Wear metals are higher than the averages almost across the board, especially Iron, viscosity has already dropped to below the range, flashpoint is low, Zinc and Phosporous levels (that protect the valvetrain) are below 1,000 PPM and you'd like to be in the 1,000-1,400 PPM range at the change interval (any higher and you can get premature catalytic converter failure).

Ideally, a TAN & TBN analysis would also be done so you can see how acidic or basic the oil is - general rule of thumb is to use a change interval where the TAN (Total Acid Number) is still lower than or equal to the TBN (Total Base Number), otherwise the oil has become too acidic and I'd bet in this sample you posted, the TAN is higher than the TBN. Blackstone may have kept enough of your sample to add the TAN & TBN to your report for another $10 or $20.

For comparison, here's a history report from one of my 997s using both Motul xcess 8100 5W/40 and Driven DT40 5W/40. Compare the Zinc, Phosporous, and viscocity #s to yours and you'll see what I mean. I'm not a fan of Mobil 1 for the reasons in your report and would move up to a 5W/40 weight also. If you live where it's really cold, you might go back to a 0W/40 for winter.

NelaK

Thanks for the insights Petza.

And you're right. That oil isn't going to be in there for much longer. I think I'll probably switch over to Motul. I can even get it a little cheaper than Mobil1 so that's nice.

By the way - is there some breakdown of what the various metals mean? For example I'm assuming that things like aluminum, chromium, iron, nickel are all wear metals and these values will go up over time with wear (You want to see these values as low as possible). There's also additives which will go down over time as the oil is 'used up' (These values should remain high)? Is it roughly organized like that from top to bottom or am I misunderstanding this completely.

Petza914

I actually don't know if they metals are in a meaningful sequence in the report listing. Silica is usually dirt, but you can get an artificially high reading of this if you used silicone or RTV to reseal something like an oil pan. Copper can be bearings.

NelaK

After a bit of googling I found this (http://www.certifiedlabs.com/certifi...s_Handbook.pdf) which seems to have lots of really useful information

Aluminum - Used in our blocks, pistons, bolts etc
Chromium - Used for rings, liners (Not in the Cayenne), valves and bearings
Iron - Used all over the place
Copper - Bearings
Lead - Bearings
Tin - Bearings
Molybdenum - Anti-wear additive. Also alloyed in bearings and piston rings
Nickel - Silicone carbide is dissolved into a nickel solution and then applied to the cylinder walls as part of the Nikasil process. The nickel may be measurable on new engines but it'll be rubbed off leaving the silicone carbide coating.
Manganese - ???
Silver - Not used in our engines
Titanium - Used mostly in aircraft engines
Potassium - Additive in anti-freeze or contamination from road salt
Boron - Additive in anti-freeze and also an anti-wear additive
Silicon - Dirt contamination, silicon gaskets wearing away and the silicone carbide lining on our cylinders
Sodium - Additive in anti-freeze or contamination from road salt
Calcium - Detergent additive
Magnesium - Detergent additive
Phosphorus - Corrosion inhibitor and anti-wear additive
Zinc - anti-wear/anti-oxidant additive
Barium - ???

So essentially:
- We always want to see low aluminum, chromium, iron, copper, lead, tin
- Molybdenum could be piston rings (not 100% on our piston ring's composition) but this depends on how the value deviates from your oil's additive package. My car had 0w40 Mobil1 which has a Molybdenum count of around 74. Which is exactly what my sample has.
- Nickel is mostly irrelevant except on new engines
- Potassium, Boron, Sodium, Calcium, Magnesium, Phosphorus and Zinc are all additives and will probably remain around the virgin oil sample's values over the life or drop slightly.
- If potassium or sodium are really high then you possibly have a coolant leak somewhere.
- Silicon could be meaningless (contaminated sample) or devastating (scored cylinders). Probably the single most important value to watch. Mine is a little high but not high enough to worry about. I might do an oil change and then send off another sample just to rule out contamination when I was taking the sample.

Everything but the silicon values on my sample seems to be in line with the Mobil1 oil and additive package.

Based off the results, I kind of want to say that I DO NOT have scored cylinders but I also don't want to jinx it by celebrating.

Edit: Kind of irrelevant but I kind of wonder what if any impact the nickel coating has on the engine. For example if the engine is run hard before the nickel has properly worn away and revealed the silicone carbide - will that potentially cause issues down the line? How long would it even take for this coating to be worn off by the piston rings? What about the areas where the piston rings won't touch? Does it just remain there forever? If it does, since the cylinder scoring tends to start in the areas where the piston rings won't reach - could seeing nickel in a worn in engine's sample be a potential red flag?

Petza914

Great info. Thanks for the research.

NelaK

By the way - for anyone reading this. I got an oil analysis report back on a different car (my 924S) from Oil Analyzers Inc and I have to say - while Blackstone Labs might be the most popular option, I definitely prefer the report from Oil Analyzers Inc. The results are much easier to understand. Turn around time was just as fast as Blackstone (essentially as soon as they get it), and they are cheaper.

They seem to be a division of Amsoil and it was my local Amsoil distributor who sold the kit to me. They also have multiple locations in Canada and the USA which means shipping is quick and cheap.

Edit: They do test slightly differently. For example they include TAN/TBN in the standard testing but they don't show Flashpoint which Blackstone does. They also test for a couple other metals.

Petza914

Can you post up that report so we can see the differences?

NelaK

I can!

In this case, this car was recently purchased and I have no clue on it's total miles, miles since the last oil change or even what type of oil was used. I'm simply establishing my baseline.

Also - if you view the report on their website, you can click on the various fields to get more information. For example they will detail their exact testing procedure, its limitations, and of course possible sources.