Power Steering Leak at the Rack - Used or New Replacement

Hi, I've discovered I have a power steering leak on my 6MT 2012 Cayman that seems to be coming from the steering rack. I see the leak at the driver's side front wheel, especially when I turn the wheel left full lock. I see posts about similar problems pointing to the High Pressure PS line failing, which is leading me to question whether its the steering rack or the high pressure line. Does anyone know how I could differentiate between a Hi Pressure hose problem and a problem at the steering rack? If it is the high pressure hose, would the rack need to be replaced anyway? If I need to replace the steering rack, is it a bad idea to go with a used rack that has been tested for leak or is that asking to see this problem again sometime in the future. Should I just go ahead with a brand new part? Is this something that a fairly competent DIY-er can do at home? The most challenging project I've done is installing a front sway bar on another car, which required dropping the front subframe. Any help is much appreciated.

Before you consider replacing the steering rack, start with this simple procedure You may have to remove the driver side wheel liner (don't remember..) as I did this procedure on my '07 CS, but it is very simple to check. Check where the two hydraulic hoses connect into the steering rack, there is a small metal plate, held by a nut (or bolt..?) that holds the two hoses into the rack, remove this plate and pull the hoses away from the rack, replace the o-rings and reassemble in the reverse order. PS: Don't remember if the o-rings are 'viton' (green color) or not, but if you buy them from the dealer, you will get the right ones

I will try that. It looks like the part number for the replacement o-rings is 997-347-945-00

I’m going to continue investigating the issue. It looks like there’s a leak in front of the rear driver’s side wheel as well. This makes me think that maybe it’s one or both of the hoses leading from the pump to the steering rack and that the O-rings or hoses need to be replaced instead of the steering rack (which would be preferable because I’m much more confident on that DIY).

Going back to ten year + memories from my 987CS maintenance issues.. But remember that there is also a block junction for the power steering lines right in front of the driver side rear wheel, after removing the bottom cover, you will see a bronce color junction box near the door sill, I believe that this box also have o-rings. I will dig into my old pictures to see if I can find the pictures and also will look into the 987 PET and share the findings.

I did some investigation on the PS leak over the weekend. Oddly, I stopped seeing it when the car was sitting over the weekend. I jacked the car up and removed the drivers side wheel, the drivers side undertray, and the front undertray. I saw some evidence of a previous leak- PS fluid on the outside edge of both undertrays and some grease/dirty fluid at the hoses leading from the steering rack. I had my brother turn the wheel with the engine running back and forth but I didn’t see anything at the two locations I’ve noticed the leak- under the drivers front wheel and near the middle of the car on the driver side (where the lines from the steering rack meet the lines from the PS hose junction near the engine). We went back and forth and I had him turn the steering wheel to left full lock which was producing the leak in the past, but saw nothing on the driver side. I cleaned the PS hoses leading from the steering rack and will continue to check them. But I saw a tiny leak at the passenger side steering rack boot at right full lock. Just a little weeping, nothing major, but still a bad sign. If I understand correctly, this means that the steering rack needs to be replaced? TLDR: couldn’t find a leak on the driver side in the previous locations, but saw a slight leak at the passenger side boot on the steering rack. Very confused.

The steering rack boots can hold a LOT of oil before it becomes evident outside the boot. Reach under the car and give each one a gentle squeeze, if one is full of oil, you'll know it rather quickly. A bad seal isn't a reason to replace the rack, and a clever mechanic can probably replace the seal with the rack in the car, but I don't think it's awful getting the rack out of the car. And seeing a drip from a boot doesn't necessarily mean the seal behind the boot has failed - have you followed the path of the drip? To really find the source of the leak(s) I'd suggest spray baby powder https://a.co/d/7dJaBKa (Amazon link). You want to clean the entire area you're investigating, I'd suggest using dish-detergent in water to do this (dish-detergent is made to break down oil and greases). Then after it dries, poof the powder in the suspect areas, where you saw the drip and above it, and to either side of it. Then go for a short drive at not high speeds. If there is an actual oil leak, it will leave a trail in the baby powder you poofed on the steering rack, lines, etc.. and the end of the trail is typically where the leak can be found. Good luck!

If you have evidence of a leakeage from the hoses at the rack, first try replacing the o-rings as this is the easiest (and cheapest) solution. However, if you indeed have a leaking rack, instead of installing a used rack (with used seals..), I would rather remove the rack replace the seals, removing the rack is straight forward as you don't have to remove the entire subframe, just loose the front bolts and remove the rears (leaving the subframe hanging on the front bolts), this would allow to remove the rack. I have a similar problem with my daily driver ('06 Volvo V70), and I found a 'local' company that replaces the seals and high pressure test the rack to ensure proper operation, the quote was about $400 which seems a bit steep (SoCal..), but they do it in one day, it comes with warranty, and it is definitely cheaper than buying a new rack..

Thanks for all your help so far everyone. @deilenberger I tried squeezing the boots but did not feel any liquid. Maybe a good sign. I was also able to reproduce the leak again today. Not sure why it didn’t happen this weekend with all the undertrays off, other than the fact that it makes everything more difficult. I was able to identify the source of the leak in the middle of the car. I’m attaching a picture of the hose with a (poorly drawn) arrow pointing to it. It is the lower hose in this picture. I’m still trying to identify the part number for this hose. I’ll have to figure out where it’s coming from/going to see if it’s possible for me to replace in a garage. Does anyone know the part number for the line in the below picture or have experience replacing it? As far as the leak at the front, it seems to be coming from a hose, although I can’t find the exact source. I may try the baby powder method. When I looked while my girlfriend turned the wheel, it seemed to be coming from above the metal crimps where the rubber hose starts, but I don’t think there’s anything up there so I’m quite confused. It makes quite a mess now and is a mist of PS fluid, so it’s hard to see where it’s originating. Here’s a (not great) video of the leak at the front: Here’s another one: If anyone spots anything that points to the origin let me know. For now, I’m thinking it’s coming from one of these 2 lines leading into the steering rack, but I can’t identify the exact point or which one it is.

On the second video you can see that the locking plate that secures the two hoses into the rack seems to be dry. IMHO, it seems that the high pressure power steering line has failed, specifically on the crimped section where the rubber hose meets the metal tube that connects to the rack. You may want to remove the front wheel to have a clear view, but for what we can see, it is the hose that failed, Porsche sells the hose that connects the rack with the distribution block ahead of the rear wheel but not sure if P/N 997-347-451-14 is the correct one. I would suggest calling Luke at Sunset Porsche with your VIN and ask him to confirm if this P/N is for the high pressure hose that connects to the rack. PS: That hose assembly should not be difficult to replace

The typical failure of these types of high-pressure hoses is weeping around where the hose is crimped into the fitting. With age, the rubber in the hose loses resiliency and starts to shrink, allowing the power steering fluid to push out of the fitting. If you're doing one - do them all. The ones that aren't leaking are just waiting to be disturbed and start weeping.

Ok, thanks for the input. From what I’ve read it’s typically the high-pressure hose that fails so this all matches with my initial thoughts. My plan was to do all the hoses in the front as well as the one in the rear that’s leaking. Now to find the P/N for the hose in the rear. I’ll give Sunset Porsche a call and see if they can help.

The P/N I found, was from the Sunset Parts website, you could search for the P/N's and then call Luke to confirm fitting 😀

Your videos are no longer showing, but I was able to dig them out on YouTube.. On the 2nd one: What's going on there? Is that a transition to a plastic or metal pipe? Is something broken? We need clear photos of the area. LEAKS tend to travel down (gravity sucks).. so the highest point you see wet should lead you to the source. For future reference - no need to add a media implant to post YouTube videos here. Just copy the entire YouTube URL and paste it right into your message and voila! Video! I'd also ask that you please read the message/link at the top of EVERY page on the site about posting photos...

I’m not sure of the material, but yes it’s a transition to a metal or hard plastic pipe leading into the steering rack. I haven’t been able to find a trail of fluid or anything. When I reproduce the leak while under there I see a spray/mist that seems to be coming from somewhere in the rubber hose portion of the high pressure line behind the metal crimp. Since it looks like it’s coming from the high pressure hose and the second leak is from the pressure hose in the rear I’m going to replace those as well as the return hose in the front. I’ve ordered all three hoses and the power steering hose release tool: High-pressure line (front): 997-347-451-14 Lower Return line (front): 987-347-449-13 Pressure Hose (rear): 9A1-347-443-17 PS Hose Release tool: 000-721-978-00 I’ll keep that in mind about youtube videos and I gave the photo posting guide a read. I’ll try to remember that going forward.

I replaced the front 2 hoses on my car. Thanks for all the help everyone. I’m still looking into doing the rear pressure hose but it looks like you need to remove the AC Compressor to do that so I will likely take it to a shop for that one. I wrote up a DIY guide on replace the front hoses. Hopefully it helps someone else in the future. https://www.planet-9.com/threads/987-power-steering-replacement-diy.257445/

Great write up! Thank you for sharing your comments, and congratulations on your repair!