I just bought a 987.2 S. Please help with my oil leak.

Hello all. I just bought a 987.2 S. Here she is waiting in line to get on the ferry to get home. 2200km journey later she at her new home. t's a 2010 Cayman S 6MT. High milage, 220K km (136K mi). It has the following options: 220 Limited Slip Rear Differential Lock 475 PASM 619 Bluetooth Interface for Mobile Phone 639 Sport Chrono Pkg W/Out PCM 810 Floor Mats in Interior Color 870 Universal Audio Interface AP Black Sport Seats P75 BiXenon Headlights w/Dyn Cornr P77 Leather Sport Seats X1 Arctic Silver Metallic Single owner. No PPI. Owner had all maintenance records, oil sample analysis, and gave me a thorough brief as to the next scheduled maintenance event. Drove it home (2200 km and 1 ferry ride) over the course of 2 days in non stop rain (thus not that many pictures). Things I have noticed on the drive: Shifter has play. Most likey will change out the shifter cables. Might just go with the Numeric vice the updated OEM one just cause it's cheaper. That little updated bell crank from Porsche has a lot of P-tax on it. Might have a slight exhaust leak. Haven't had time to put it on the hoist yet to investigate. Brakes drag ever so slightly, don't know if that is normal. It's got plenty of power. PASM is really cool. I can't tell if PSM has saved me yet but I feel like it helped me out in standing water. Feels really refined and almost isolated from the road. No where near as raw or road feelish as my air cooled 911. Good highway crusier. One is a space shuttle, the other is a rocket sled? Water cooled is really nice for things like HVAC and demisting. I may do the android head unit, I may not. Silver is my second last choice in colours. The seats don't have enough adjustments but are decent enough. I enjoyed driving it. She did quite well in torrential rain with not much tread on the rears. I paid 30K CAD or 22 USD. I then got it home and opened up the engine bay.......

Here are some pictures of my oil leak. Any guess where it could be coming from. Judging from the build up it has 1) been happening for a long time, and 2) Is a very slow leak.

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Oh my. Welcome to Planet-9. I guess this is why we always suggest a PPI when buying remotely (and sometimes even when buying locally..) That's quite the mess. I typically wouldn't suggest the use of a high-pressure washer on an engine compartment (gets into the electrical bits causing corrosion in the connectors and such), but in this case? Maybe used very carefully after soaking down all the munge with some solvent engine cleaner. Then got at it with some disposable wheel brushes. It's about impossible to even begin to guess where the oil leak originates with that amount of buildup in the engine compartment. It might be something as simple as a cracked hose in the breather system.. or a bad valve cover gasket, but until we can see what's under there I can't really suggest anything to try. BTW - moved your thread over to a technical section of the 987 forum.... a better fit there than in the general "chat" section..

If you have a shop vac that won't be sullied by the effort, perhaps try to vacuum some up first, unless you're outside where it doesn't matter. As for PPI, hard to miss that even as a novice. 220K any receipts for an AOS ? That looks like an intake leak to my eye.

I usually get one as well but this time I just took my chances with the seller, history, age of car..etc. I got a PPI done on a 996 just before and it was rather disappointing. Not the results but the actual PPI. I didn't want to disturb it in case someone wanted to see something untouched. I plan to clean it up and try to find the source. Other than the ergonomics it doesn't look bad to get at that stuff. I have a nagging suspicion it's somehow AOS related. I think I will also take the opportunity to bore scope the intake valves to see if there is any build up.

I like the vacuum idea. It will probably be a combination of plastic scrapper and vacuum until I get to metal. No receips fro the AOS. I thought about intake as well but aren't intakes under negative pressure? They leak inwards not outwards?

It's hard to shoot darts from the internet. If the AOS isn't performing correctly, it can dump oil into the intake, at least that's my understanding of that system, someone else jump in if I'm misremembering. At that mileage it's going to need one anyhow so its not blind replacement and prayer as much as sorting what will need attention anyway and working from there. Once that's clean as Don noted it will be easier to track down.

At 136k miles - the AOS is certainly a suspect, and the plastic connecting hoses (as I'd mentioned) - but you have to see them to analyze them. I'm looking forward to equally as good photos as you unfuzz the engine..

I agree with all these comments. While it’s hard to tell exactly what is causing this, the course of action seems fairly clear. Clean up the engine compartment. Replace the AOS as an maint item, and clean related breather hoses. Then see where things stand. In terms of cleaning, I think the shop vac for the big chunks is a good start. Perhaps a bit of scraping afterwards. Then an engine cleaning product. Gunk makes a fantastic one called Engine Cleaner and Degreaser. It’s safe on metal and plastic. You can spray it on. Then agitate lightly with toothbrush. Then spray off with a hose on a mist setting being careful to avoid wiring harness attachment points as much as possible. And congrats on a really special and rare car. The 987.2 in a manual is fantastic. Having only a minor issue like this speaks highly of the quality. The experience behind the wheel is truly the sports car sweet spot. 🏎🏎

For the record, there's no need to be crazy careful washing an engine. They're designed to be reasonably waterproof, and there's a saying that "anything in the engine compartment that stops working if you get it wet needed fixing anyway." As long as you're not using a pressure washer or really strong stream of water or getting water into the intake (which really can't happen from the Cayman engine bay) then you're fine. So get a can (or two, lol) of Gunk Foamy Engine Cleaner, a hose with a shower nozzle, and go to town. You're not going to figure anything out until you clean all that crap off.

Thanks all for the help and suggestions. I think I am going to delay a bit digging in until at least my new scanner comes in the mail so I can get some base readings before in. But while I have you all here. I noticed the water pump and coolant has never been changed. Should I change the pump or just the coolant? Any thoughts to Numeric vs upgraded Porsche shifter cables? I've got to change the transaxle oil. There's nothing super special about it, correct?

A couple of quick thoughts: 1. this is supposed to lifetime coolant, but not a lifetime water pump. many videos show people reusing the same coolant, assuming it is clean. at 220K, I'd be more inclined to replace it, and the water pump 3. use the Porsche fluid- there are posts about this on this site, but that was the strong consensus. the job itself is pretty easy.

Wow, I have never seen an engine this dirty.. if this was my new car, before anything else I would do it in this order.. 1) remove all the extra crude (junk) with a plastic spatula or flat screw driver, as much as possible 2) buy at least two cans of heavy duty engine degreaser (before you apply it, get the floor wet so the junk won't stick to the floor, then use the degreaser and try to use a soft brush on the stubborn stains.. 3) rinse from the top with "Very Low" water pressure (so you don't force any water inside the connectors), you may have to repeat step 2.. 4) after you are happy with your now clean engine, use diluted 'Simply Green' to remove all the engine degreaser residue and then rinse again with low pressure water. Note: I have used this engine cleaning procedure for many years in different cars (including the Cayman ), and the key is to use low pressure water to rinse the engine after using the degreasers Then, you can start looking for the cause of the oil leak.. Good luck, and congratulations on your new ride, you are going to love it PS: For the transmission I would suggest using the Porsche transmission oil

I would definitely replace the water pump and thermostat. They are maintenance items and the mileage has exceeded the sevice interval. I’m not sure there is an official service interval, but 100k miles has always been a cutoff I’ve used. If you are keeping the car a while you might as well do it proactively. In terms of shifter cables, the Numeric are the best in terms of durability and tighter feel. But they create a bit more NVH. The new Porsche shifter cables have been redesigned a bit (the brackets) to create less stress on the cable. I used the Porsche ones as I didn’t want the NVH, but I have only had them for about 2.5 years and 9k miles so hard to gauge their durability.

AOS question. Is it just the AOS or the ancillary pieces as well. I noticed FCP et all sell kits that have few pieces. What should I replace besides 'what's broken'. The kits don't seem to include the last one for some reason. 9A110704201 Separator 9A110503800/00 Crank case vent valve L and R 9A110752001 Breather hose 9A110751501 Other breather hose 9A110738301 Some other separator?

When I did mine, I replaced the AOS and the breather hose. My AOS part number was PB-115-099-A. I believe the current one ends in a B. They always seem to revise the AOS . When I did mine, I ordered only the AOS and then inspected the remaining parts as I was doing the replacement. In my case I decided it would be easier to replace the breather hose (9A110752001) than clean it so I ordered that afterwards. Depending upon the condition of your AOS , the remaining parts may not need to be replaced or they might be easy to clean.

Yes, this is the same part number that I see the previous owner bought a couple years ago for my 09 Cayman.

Okay, next fun question. Why does Porsche use 2 part numbers for what seems the same part? 9A1.107.042.01 and 0PB.115.099.A. The first one seems to follow the normal Porsche nomencalture the latter does not.

Before you throw parts at it I'd probably clean it up, see if you can learn anything. The 987.2 AOS should be a lot more reliable than the 987.1 version, but those corrugated hoses get brittle and are prone to cracking. Note that there's a vacuum measurement test at the oil fill for the 987.1 AOS , but don't use that spec for the 987.2 : the 987.2 pulls a lot more vacuum than the 987.1 version and will fail the 987.1 spec even when good. Clean off all the dirt, pull off the intake and the MAF and clean out any pooled oil, check everything for cracks and leaks. For those two big straps on the intake, make sure the rubber seal under them is intact and seated properly, and then torque the strap to spec (it's somewhere in the service manual, if you can't find it I'll look it up). If they're not fully tight the oil that gets into the intake (there's always some) can pool there and then seep out the bottom, which is what it looks like is happening on the left. Then I'd just drive it a bit and look for leaks. If you want to get clever the UV dye/flashlight kits for oil work very well.

Ya, I remember reading all about that AOS when I was shopping for a 996. I will check out those hoses to see their condition. [ I did get a feeling it was coming from the underside of the intake because that's the cleanest spot. It's why I included a picture of it. Must only leak when the engine is shut down because that area should be mostly under vacuum when the engine is running. I'll see if my cheapy scanner can pick up the fuel trims on this car. That might point to a intake leak.

It seems that the oil is coming from the left intake plenum clamp which means is coming from the AOS .. on the 987.1 there is a long 'accordion hose' that connects the AOS to the top of the engine on bank 4-6 underneath the intake runners, that you can reach (to connect) from behind the driver's seat once you remove the engine cover behind the seats, however not sure if the 987.2 has the same hose or only applies to the 987.1 IF this accordion hose is cracked, the engine will run much better once you replace it as it will restore the vacuum that these engines need to have a good seal on the piston rings. Once you clean the engine you will find the hoses and source of the leak

This thread seems to indicate I am not the only one to have experienced this problem. 987.2 C exessive oil in air intake plenum Hi All, A few days ago I noticed oil drip on the garage ground. I opened the engine lid and found exessive oil on the heat exchanger just below the air intake pelnum, then the engine bock, as well as the other side of the plenum. I took off the plenum and found tons of oil inside the plenum. I... www.planet-9.com For anyone who searches this in the future 987.2 plenum torque spec is 3.5 ft-lb, 5 Nm and the vacuum -15" H2O I have some cleaning to do!

So I finally got to it today. This is the AOS tube. Seems in good shape with not cracks. The engine before cleaning. The engine after my mediocre cleaning. I figuired I would just vacuum the debris and it work out quite well. The little layer left behind won't hurt anything and it really doesn't bug me at all. I could have done the whole deal spraying, wiping, washing, blowing...etc. but that could have just made things worse. I just left it alone. I hypothesize that this is where the oil was coming form. It is the only spot I found that had clean oil on it and it is the highest point. I also took the opportunity to clean the throttle valve and MAF. Car feels smoother now. Oddly enough shifting in the garage with the engine off now makes a bit of a tin-y sound. Not sure if that was there before. If I notice it driving I will investigate further.

I also took the opportunity to scope the intake valves. It's dirty down there. Camera kept picking up oily goo on it. It's not clean. I think at some point I may have take the intakes off and clean the valves and intake runners. Maybe I do need a new AOS or maybe I need to install a catch can. For your viewing pleasure. I think I took pictures of 3 different valves randomly. They all look the same. And if you're wondering about the mileage and life of the car my scanner showed up in the mail today. Car has just over 3000hrs and 220000km. That puts the average speed at 73km/hr. (Or in freedom units: 136k mi at an average of 45mph).

The valves do need attention. That's one big drawback to direct injection. Other manufacturers started putting a second set of injectors in the intake again just to keep the valves from crudding up.. that's about as bad as I've seen. Betcha' it would make a big difference in both idle/smoothness and performance to get the crud off. Someone did a writeup on a DIY of cleaning them, complete with a 3D-printed fitting for the intake ports to let the blaster in to do its work while a vacuum pulls the result (and walnut shell chips) out. I think a bit of searching might turn that up here.. (unless someone remembers where it is.. and posts it..)

I would definitely replace the AOS based on what you are seeing. It's the doorway to all the oil coming to the intake. A catch can would be a secondary step if a new AOS doesn't help. And only usually necessary if you are tracking the car. You might also check the oil level. Having it too high may cause these problems. It might be that the previous owner had the oil level too high. I try to have the oil level indicator no higher than 3/4 of the way up. I also live in Maryland and the moderate temperatures allow me to use a 5W-50 oil rather than 0W-40. By going with a slightly thicker oil, I make it a bit harder for oil to get past the AOS . But if I wasn't tracking the car, I would likely use 5W-40 rather than 5W-50. Of course, important to use a good quality oil. Agree with Don about the walnut blasting. Those valves look quite icky. But great OBD reading with no overrevs.

Ya, I am slowly gathering a list of stuff to buy so I can save on shipping. AOS will be on there. I will swap it out same time I do the valve cleaning. Probably won't do the catch can. I might also combine it with shifter cables which will make everything even easier. PO ran 0W40. Told me he always kept it at the 3/4 except for the last change where it some how got to 4/4.

Probably is good to ditch the catch can idea can as these engines are designed to work under certain vacuum.. IMHO, changing the AOS and cleaning the valves will get your engine working within the OEM design parameters. Regarding the engine cleaning (sorry to bring it up again..), if you don't want to make a mess on the floor, you can clean one side of the engine first, I have a large plastic tray that I had used with a bit of cat litter sand to catch the drifting junk from the engine degreaser's (the oily mess man easily be put on a trash bag) thereafter you can remove the oily film from the engine degreaser with simply green and rinse with water as this will no longer get your floor dirty. You will be happy with the results 😁 PS: Regarding the valve cleaning JRichards put an awesome video on the 981 DIY section.

Vortex, which camera did you use to take the pictures of the dirty valves?

Gilles is on it with this method! I lean towards low pressure compressed air before water Congrats on the direct injected Cayman it will take a bit to get it up to snuff but I think you still got a very good deal, I have 128k miles and it's clean and runs strong. My advise is. Change ALL the fluids ... it has not been service in a very long time if ever at least not by a pro. I do go to a Porsche only Independent which I would advise once you get it cleaned up to get it right and fix everything that is wrong and you do want it right if you are going to drive it the way it was meant to be driven also an Indi will use the correct parts and premium fluids then after you get it right you can do your own service if desired.