Howdy, I’m loving this forum, thanks all! I wanted to get together a good list of proactive maintenance for aging 957 CTTS (and closely related brethren), especially for new owners.

This is meant to supplement the “so you want to buy a Cayenne, read this first….” Thread). Or maybe to add to the DIY section as a summary and reference to these various procedures. I plan to edit this first post/list as significant changes and recommendations surface…

Your advice encouraged and welcome! This is based on my personal plans and things I’ve noticed from reading about others’ efforts - thanks forum dudes!

So far we have:

- start with the “so you want to buy this…” thread for other key recommendations: coolant leaks especially.
- brakes as needed ($$$)
- suspension bushings likely want refresh all around or upgrade to poly ($$$$)
- PASM dampers seems to be regarded as ok long term and too expensive ($$$$) to refresh prior to failure (unlike other traditional dampers where it is likely very noticeable to refresh). steel spring non PASM might be worth refreshing dampers?
- alignment (Firestone lifetime is $200, free thereafter)
- all fluids and filters: oil, f/r diffs, tsfr case, pdcc, power steering, coolant, brake fluid.. ($$$) (personally I plan to replace all fluids a couple times or more ahead of schedule, before settling in. thanks FCPeuro for lifetime replacement policy making this cheap to repeat!)
- spark plugs ($)
- fuel injector cleaning (thoughts on in-car treatments vs removing and running carb cleaner through them on the bench?) ($)
- valve cleaning (thoughts on walnut blasting vs in situ like BG?) ($-$$$)
- engine air filters
- cabin air filters
- wipers
- (hood and hatch struts as needed)
- those damn windshield washer fluid caps that rot lol
- coolant reservoir cap as insurance against a clogged vent hole in the cap causing expansion tank rupture
- a/c recharge?
- check turbos for leaks especially charge pipe o-rings
- check intake, spark plug, cam adjuster, and valve cover gaskets for leaks / proactively refresh if you are in there for any reason, like for coolant tees or spark plugs, etc.) ($$)
- likely diverter valves, especially if not making full boost (anything less than needle past the .8 most of WOT), but that is a whole thing to diagnose and chase down… ($)
- likely going to want to do things like switch to silicone hose and brass tees and fittings for vacuum control and PCV circuits - they get brittle and develop hard to find leaks over time. (Any advice for cleaning out various circuits from accumulated blow by, like with simple green or other? Is that a dumb idea?) ($)
- consider adding a catch can ($-$$)
- any chassis lube points or other things like that?
- check body/roof drain ports and consider cutting them with scissors so they drain easier and less likely to clog (I plan to keep oem as fording a river is a likely future endeavor…)



…. Anything else you would add to show a new-to-you pig some love?


Personally I am especially curious about recommendations on engine stuff like plugs, injector cleanings, valve cleanings, and anything else to show some love and pride of ownership.

 

I reordered your list and adding comments with *****



- check body/roof drain ports and consider cutting them with scissors so they drain easier and less likely to clog (I plan to keep oem as fording a river is a likely future endeavor…) ****priority #1. Many numerous headaches can be avoided all together.

- all fluids and filters: oil, f/r diffs, tsfr case, pdcc, power steering, coolant, brake fluid.. ($$$) (personally I plan to replace all fluids a couple times or more ahead of schedule, before settling in. thanks FCPeuro for lifetime replacement policy making this cheap to repeat!) ****good plan

- spark plugs ($) *****get coils too, these vehicles are picky so get BERU only.

- those damn windshield washer fluid caps that rot lol ****I replaced mine with the newer VW light blue, its a different plastic - VW part # 1H0955455

- coolant reservoir cap as insurance against a clogged vent hole in the cap causing expansion tank rupture ****replaced mine with VW part but porsche just as inexpensive
- engine air filters ****remember you'll need 2

- cabin air filters **** BOSCH makes a good one

- wipers ****BOSCH again, icon is great

- likely diverter valves, especially if not making full boost (anything less than needle past the .8 most of WOT), but that is a whole thing to diagnose and chase down… ($) ****itll be worth it though

- consider adding a catch can ($-$$) *****i think everyone should have one on the turbo engines

- brakes as needed ($$$) *****the fronts rotors are obnoxiously expensive 2 piece unique units.

- check turbos for leaks especially charge pipe o-rings

- check intake, spark plug, cam adjuster, and valve cover gaskets for leaks / proactively refresh if you are in there for any reason, like for coolant tees or spark plugs, etc.) ($$)
- (hood and hatch struts as needed)

- suspension bushings likely want refresh all around or upgrade to poly ($$$$) ****for the price of bushing plus uninstall and reinstall, it might just be easier to replace with totally new parts, including aluminum lower control arms from the Q7 if you can find them

- alignment (Firestone lifetime is $200, free thereafter) ****Do this after/if suspension update, no sense in doing it unless you have severe impending unaligned wheels

- likely going to want to do things like switch to silicone hose and brass tees and fittings for vacuum control and PCV circuits - they get brittle and develop hard to find leaks over time. (Any advice for cleaning out various circuits from accumulated blow by, like with simple green or other? Is that a dumb idea?) ($) ****the pcv system on this runs on super high heat and oil exposure and subject to vacuum. the lines are hard plastic for a reason. FCP euro sells a whole PCV refresh kit for $900 or so but you can likely piece meal out cheaper

- valve cleaning (thoughts on walnut blasting vs in situ like BG?) ($-$$$) ****Check my 219,000 mile Turbo S before going down that rabbit hole

- PASM dampers seems to be regarded as ok long term and too expensive ($$$$) to refresh prior to failure (unlike other traditional dampers where it is likely very noticeable to refresh). steel spring non PASM might be worth refreshing dampers? *****you can get the whole air shock for cheaper than just replacing the dampeners on these. see arnott

- fuel injector cleaning (thoughts on in-car treatments vs removing and running carb cleaner through them on the bench?) ($) *****as long as you are running good gas, i don't think this is necessary

- a/c recharge? ****only if the cooling performance is negatively impacted

- any chassis lube points or other things like that? ****if its squeaking unfortunately the bushing is probably bad. these have very shall we say, competent but not very robust suspension bushings[/QUOTE]

 

Adding:

- clean throttle body
- replace drive belt

https://pictures.dealer.com/porscheo...c2488218cb.pdf

and

https://www.pcarwise.com/local-help/...ance-schedule/

 

The throttle body will forever have trace oil in/on it, but as long as its not gunky & carboned (mine wasn't) its good.

 

Never, ever, EVER let Firestone touch your Porsche.

This should be added to the sticky I guess, idk why this even needs to be said. Firestone is TRASH