jimmiepop

955 is the first gen Cayenne; 2003-2006. Yes; TT is twin turbo

Confirmed.

My understanding, from those more knowledgable than I, is that the issue is diminished piston clearance in cold weather due to the difference in the coefficient of expansion of the piston and cylinder materials. You probably already read these, but a couple relevant threads are -

https://rennlist.com/rennforums/showthread.php?t=801417
https://rennlist.com/rennforums/showthread.php?t=799450

Jake at Flat6 is the resident expert; and extremely helpful. (https://rennlist.com/rennforums/member.php?u=91015)

The stickies at the top of the forum. (https://rennlist.com/forums/porsche-cayenne-forum-77/)

My short lists were -

Repair Inventory
Coolant pipe (MUST be replaced/upgraded; $1800)
If replaced, was it replaced before it blew?
Front Transmission Seal ($2000; likely if coolant pipe blew before replacement)
Cardan Shaft ($800)
Water Pump
Fuel Pump
Rear Turbo Pipes
Control Arms
Coils
Air Compressor
Hood Struts
Rear Hatch Struts
Horn
PCM
DME Transmission Control Unit


PPI
Coolant pipe (MUST be replaced/upgraded; $1800)
If replaced, was it replaced before it blew?
Front Transmission Seal ($2000; likely if coolant pipe blew before replacement)
Cardan Shaft ($800)
What would it need to pass the Next (likely 80K) Porsche Scheduled Maintenance
Compression Test / Leak Down


My understanding is that there is a very strong positive correlation between cold winter temperatures (and the consequent cold starts, where engine damage occurs) and piston scoring in the V8. Scoring seems to be rare, but does occur, even with the turbo, and at $30k for a rebuild, strikes me as a nontrivial consideration. After considerable research, I decided that the purchase risk could be largely mitigated by purchasing a car from a warm climate and purchasing a turbo (greater piston clearance). I also invested in a full PPI, including compression test and leakdown.

The best solution I found for operating in a cold climate was the webasto parking heater (here and here. I believe that I recall reading that this was an option on the the euro models, and perhaps in the U.S. also. In several months of shopping, I did not come across a single U.S. Cayenne with the parking heater. I believe that Webasto sells an aftermarket parking heater for the Cayenne in CA, UK, and EU, but not the US.

Cole

Fwiw, some of those items listed above are fairly easy DiY for a fraction of the cost listed.

porschefan931

No issue with cold here, and i don't have a block heater. I have an '06 TT with E-81 powerkit and 255,000km's, spent all it's life in Alberta commuting between Calgary and Grande Prarie. I my 8 months of ownership i've only replaced the transmission seal, everything else had been done.

As long as you know it's been looked after, you shouldn't have any issues.

Sniffer

On the 6 cylinder 3.0i X5? Sounds like that "issue" affects ALL X5s

Another vote for the Turbo variant - I think thats the direction I`m headed

Sniffer

I didnt know that - I had read the sticky about the years but it made no sense until I saw this - thanks for the info

Sniffer

I know that feeling!

Its reassuring to hear that from someone who's had both - whatever I get next reliability needs to be significantly improved over the X5 and it sounds like the Porsche fits the bill

I had heard Range Rovers were a bit of a disaster zone - my father in law had a Land Rover Discovery (which is very similar under the skin apparently) and it was a money pit

Sniffer

Good info - and another point that needs to be checked when searching for the "one"

Sniffer

I`m glad I stuck around - the Nissan wasn't an option though…..

Those are impressive mileages and more like what Ive came to expect from previous German vehicles that have been looked after

By all accounts the Turbo is the one to have, good build quality, most "oomph" and a high spec as standard

Whats not to like? Except the thirst…. Just how bad is it?

Sniffer

Interesting - can I ask how many miles out of curiosity?

Sniffer

LOADS of good info there - that`ll keep me out of mischief for a while

Thanks!

Sniffer

I`m pretty competent with the wrenches so thats something I may dabble with (time permitting)

Are we talking swapping the coolant pipes and Ts etc or something else?

Sniffer

Wow, having been to both Calgary and Grande Prairie thats a long commute, and the roads at GP leave a lot to be desired….

So is it worth getting a mechanical inspection done on any potential purchases to weed out the gremlins? Is that normal or not?

wrinkledpants

I've owned a lot cars, and "reliability" is a highly subjective term. I think most people associate that word with "cheap to operate." So, while the Cayenne is actually quite reliable, it's not exactly "cheap" to operate. When you combine the insurance costs, frequency of tire and brake replacements, gas mileage, and average cost of the few parts you might have to replace, I would guess you'll spend more on a Cayenne than you will on the X5. That will be especially true if you aren't in the DIY camp for maintenance. For me, though, reliable needs to be combined with capability and how complicated the car is. I've owned 3 hondas, and I replaced head gaskets, exhaust manifolds, window regulators, various interior back lighting, axles, stuck calipers, and a plethora of other parts that were cheap to buy, and cheap to have someone replace them. You can drive those cars knowing they have issues, and it's totally fine. People associate those cars with the term "reliable." To me, the Cayenne is more "reliable" but not as cheap to own. It's 450 HP, goes off-road better than most SUVs, handles as good as a B6 S4, tons of technology in it, and it's built like a tank from a safety standpoint. My guess is that if you buy one that's well maintained, you'll have fewer problems than an X5, but the problems you do have won't be as cheap to fix.

The Cayenne S is has the V8 with the scoring problems. The GTS and Turbo don't have those issues.

Coolant pipes are a 1-time fix
Driveshaft to the rear diff (cardan shaft) is anywhere from 400-1200 for the shaft, and a few hundred in labor if you don't do it yourself (it's pretty easy to DIY). This is every 60-100K miles as it's a wear item
Brakes are every 20-40K miles and are roughly 1500 in parts to do all wheels
Tires 20-30K miles and prices are all over the place
Front lower Control Amrs: 580 for the arms and hardware, and can be a DIY project as it's pretty straight forward. Figure another 200 for an alignment. Or, 12-1400 total price to have a dealer or shop do it (parts and labor). Those seem to fail around 100K miles. Again - this is a wear item, not a problem area.
Coolant fittings (2 T-fittings on back of motor). They're plastic and will eventually fail. Cheap to replace, but hard to get at.
Rear hatch struts seem to fail every 6+ years with 60k+ miles. 150 in parts and not a fun DIY, but not bad, either.

That's it for the "common" issues. Less common, but still kind of common

Transmission Valve body - $650 for a rebuilt unit and it's an easy DIY. Otherwise figure $400 in labor. More common on the 04-05 models.
Transfer Case Stepper motor: a small electric motor that's roughly $500 to replace. Super easy DIY.
PCM display: can have them repaired for a few hundred, or replaced with new for a few hundred more.

The motor itself is pretty solid. You don't often hear about turbo failures, block issues, or accessory failures - at least on the Turbo. Air Suspension is solid - rarely hear of issues aside from the bump needing a rebuild (cheap and easy to do). Interior holds up really well without any squeaks or rattles. On the turbo, part of this is because everything is leather - dash, door cards, everything. I believe these are options on the GTS and S. The driveline is pretty reliable, I would say. And, if you do have a diff or tranny failure (complete failure), there are plenty of cayenne in salvage yards to get a newer part used.

I like the GTS, but it's still slotted somewhere between a CS and Turbo. The interiors can seem spartan on the GTS if they're not well optioned. They look nice, and I think that's the biggest reason to get one. The Turbo is faster, gas mileage is the exact same, and it has more standard features than the GTS. I would go with the Turbo. Sure, it's a bit more complicated, but not by much. And, the additional maintenance it might need will fall well within a reasonable range of the GTS. Gas and insurance will be your two biggest expenses. My 04 CTT was purchased with 100K on the clock, and I spent 1600 in parts to get it up to speed. That's a complete fluid change with redline fluids (engine and full driveline), plus replacing a few parts, the most expensive being the control arms. For comparison, my wife's 04 Murano was purchased with 99K miles about 3 years ago, currently it has 138K miles, and we've spent nearly 6K on it. I paid 19.8 for my car. You should be able to find an 04 Turbo in the 18-23K price range. The cars I saw below 18K were either really high mileage, or had issues. Nothing wrong with high mileage, but for some reason there are far more clapped out Turbos than there should be. Even some of the Turbos I saw at Porsche dealers were in rough shape, and headed to auction if they didn't sell.

All the big ticket common part failures that are reoccurring are on both the Turbo and GTS. Cardan shaft, tires, brakes, hatch struts.

Some turbo cars are notoriously expensive to own. I would put the CTT near the top of the list for well-built cars that are in this high-performance SUV category.

wrinkledpants

I would get an inspection at a shop that knows them unless you have your own durametric cable to scan the car. They're like $350, I think.

But, if you have the cable to scan them, and you know how to check for the common issues (clunking of control arms and the car will usually pull, especially under hard braking), and you have a good eye for inspecting things, then you could bypass a PPI if the car is local to you. But, the owner would need all records, you would need a durametric cable, and you'd need to have an OK idea on what to look for. Otherwise, do the PPI for good measure.

wrinkledpants

Don't forget that the Turbo has an piston skirt oil squirter that the CS V8 folks don't have. This combined with the forge vs cast piston is what also contributes to the scoring. I've heard of blocks on the Turbo failing, but it's not for the same reason that the CS blocks get scored. Even then, the Turbo failures seem to be on par with just about any car having a major block failure. I think I could count 3 that I remember on the forums.

Good driving habits, proper oil, and staying on top of maintenance should ensure that your Turbo motor lasts far longer than you'll likely ever have the car.