Advice for first Porsche purchase, older C-TT

[Nelson_Wells]

To be honest, a Cayenne  (2006 Turbo S) was the last "first Porsche" i thought I'd ever buy, but I'm considering it.  This first Gen are old now, but there just seems to be so much bang for the buck if well-maintained.  Thanks to you all RENNsters over the years I've worked up this list.

Someone care to put it in the right order of importance for me?  Thanks in advance!  - Curious & in need of HP in Georgia.

Checklist:

1. Have coils been replaced, ?
2. rear hatch struts been replaced? 
3. Switched out Coolant pipe Plastic pipes for Aluminum pipes (was done free under warranty first 5 years?).
4. Cardan Shaft(drive shafts running to the front or rear diff (look for vibration on acceleration). Has it been done?
5. Front diffs replaced? sometimes (you will hear a fairly load humming at neutral loaded speeds)
6. Auto Tranny Solenoid replaced? (basically if it does erratically HARD downshifts
7. Battery condition?, if not kept up can cause electrical issues.

 

[Loren]

 

How many miles?

 

I would say...

Verify 3.

Item 1 should fairly easy.

Obviously, you are going anywhere with a weak or bad battery.

Item 6 - I would definitely try replacing the ATF with Porsche spec fluid and make sure it is at the right level.

Certainly check the cardan shaft and joints more important if the car is high mileage.

Rear hatch struts - if it drops on your head then they should be replaced... 

[JFP in PA]

1 hour ago, Nelson_Wells said:

To be honest, a Cayenne  (2006 Turbo S) was the last "first Porsche" i thought I'd ever buy, but I'm considering it.  This first Gen are old now, but there just seems to be so much bang for the buck if well-maintained.  Thanks to you all RENNsters over the years I've worked up this list.

Someone care to put it in the right order of importance for me?  Thanks in advance!  - Curious & in need of HP in Georgia.

Checklist:

1. Have coils been replaced, ?
2. rear hatch struts been replaced? 
3. Switched out Coolant pipe Plastic pipes for Aluminum pipes (was done free under warranty first 5 years?).
4. Cardan Shaft(drive shafts running to the front or rear diff (look for vibration on acceleration). Has it been done?
5. Front diffs replaced? sometimes (you will hear a fairly load humming at neutral loaded speeds)
6. Auto Tranny Solenoid replaced? (basically if it does erratically HARD downshifts
7. Battery condition?, if not kept up can cause electrical issues.

 

 

Rather than a check list for you, it would be well considered to have a proper pre purchase inspection done by a qualified shop, which would generate a firm list of what needs to be done.

[hatchetf15]

How many miles? Any service records? That will drive the priority. Coolant pipes a must. The hatch struts you’ll know if they don’t pop up with authority with no droop. Check the center rear hatch glass to make sure it opens. Turn on headlights and observe the leveling test. All four wheels spec’d with 275/40 20s. TTS had staggered 9”/10” standard. Tip should’ve been serviced sometime after 50,000 miles or so. Brake disc thickness because the front 380’s are very expensive. Listen to engine with with the hood up. Check some of the audio clips on RL for bore score vs. injector noise. Check to make sure every switch works. After the car is started, run the air suspension full up and full down to loading height. Check for air compressor hose under rear passenger seat (driver side). While you’re there smell for any fuel vapor. If there is any smell, the safety recall may not have been done for fuel seal. If it has the pano roof, check that thoroughly. If the battery is weak, the car may throw some weird malfunction indicators at you. These items will help you determine gold plated or money pit.

 

For the test drive the transmission should shift up and down pretty dang smoothly. Turn off PSM and check the transmission changes to sport map, starts in 1st and holds gears to redline. Try the sport mode with PSM off and the suspension low. You will be impressed.

Then schedule the PPI.

 

I love mine…

Edited January 8, 2022 by hatchetf15

[danish]

I would like to add that Cardan Shaft bracket tends to go bad every 3-5 years, unless you replace it with a better one, or install a single piece shaft, then it may last longer.
Same is the case with rear hatch struts, they go bad after a few years.  So even if they work fine now, expect to replace them in next 2-3 years or sooner/later depending on their condition.  Not to disagree with hatchetf15, but brakes condition is not something I would reject the car for but will definitely use that to negotiate the price.  Expect to replace rotors and pads every year and a half or two depending on your driving habits, so keep that ongoing expense in mind.
And as hatchetf15 pointed out, scoring check is critical, along with other points.

Coolant reservoir is another thing that breaks, so do make sure it has been replaced.

I would not worry too much about coils or plugs as Loren pointed out, they are easy and quick fixes.  And if buying a used car that has over 100k miles, I would replace plugs for sure.  If cracked, replace coils as well.  Replace engine air filters, and cabin air filter, again quick, cheap, and easy, but worth it.

Get it checked by a tech who you know and trust, and the one who works on Porsche and has access to PIWIS or has Durametric.  Also plan to buy Durametric, if you plan to own this car as it will save you a lot of headaches, and money.

[bigbuzuki]

Front brake disc rotor replacement cost is brutal.

[reyxlp]

I would add the "coolant Ts" to that list, if you wanna take the "list" approach (in addition to PPI - def get a PPI, do both is my vote lol). I bought mine CPO from dealer. Started having a coolant leak. Dealer twice denied it, took to independent who took photos to prove it. Went back to dealer with the pics, they finally admitted they needed replacing. Because of what I'd learned from others on the forums here and elsewhere, I tried to get the dealer to do the Ts while they were at it, they refused to acknowledge the Ts even existed, let alone agree to replace them-- even at my own cost, I offered to pay for that extra work. Fast forward to a few thousand miles later- woke up one morning to massive coolant puddle under car in garage, miracle it happened at home parked and not during a drive. Had it towed to mechanic- coolant Ts had failed. Ts are cheap, labor to get to them is the same as the pipes. My mechanic was willing to replace them with metal ones I found also thanks to other forum members sharing their experiences, so hopefully that issue doesn't come up again. But that friggin dealer owes me $$$ in the labor it cost me to do the Ts when I offered to pay for them while they were doing the pipes. If you stay with the factory Ts, they come as part of a hose assembly so you do the hoses with the Ts. I think there are 3 Ts.

 

The rear hatch struts are DIY, I'm beginner and did them myself using Pelican Parts DIY. My rear hatch glass struts failed around the same time as the rear hatch ones. Also DIYd using the Pelican tutorials.

 

Coolant reservoir was also an easy DIY and inexpensive part, I wouldn't dealbreak over that one, or the struts.

 

Me personally (and most might consider this excessive) but I would check for bore scoring as part of the PPI. I'm guessing it would add 1-3hrs labor cost to bore scope, compression and leakdown test but if you happen to be one who gets bit by this, it's engine replacement.

 

You've already taken the most important step by visiting this forum. I've had my Cayenne for about 10 years and the people on these forums are just the most amazing, generous community. The knowledge, advice and information are priceless. Easily saved me thousands of dollars and money aside completely enriched the experience of having one of these monsters. 🙂

 

Good luck to you!