2005-2006 Cayenne feedback
 

Thinking about a Porsche Cayenne, around 2005/6.

Why or why not choose the turbo?

What to look out for?

How reliable?

Not an immediate purchase but soon, so talk me into/out of it

Hi, there's a rumor that all V-8's have unreliable cylinder wall coating that will degrade/scratch etc with time.

"Bore scoring" I think is the technical term. Mine's at ~150k and no issues so far. I think regular oil changes with good oil help.

More like a metal used for cylinders - Nikasil. If there is indeed Nikasil, then it's the fuel composition, rather then the oils change intervals. A similar problem was with 90's BMW's - they had Nikasil problem due to US gas. I almost bought 540 back then - it didn't accelerate at all, and felt like a half-a-cylinder car. Thus, BMW had to rework cylinders with, I think, Allusil alloy, that "resisted" US-made gas and had to replace all existing engines under a warranty.
Nikasil... Why not Titanium.

The early turbos (I bought a 2004 a year ago) were made with solid alusil blocks, including the cylinders, I believe. Being a turbo, they also have the added protection of the addition of oil squirters in the cylinders. As far as I have researched, the turbos have good longevity (200-250k miles).
The downsides are the gas mileage (you must use at least 91 octane, recommended 93) at 12/16 city/highway. Also, any normal maintenance is extra pricey, unless you do it all yourself.
I justified it because I don't drive a lot of miles per year, and because I can do 90% of the work myself.
As an example, I bough mine at 92K on the odometer and have driven 11k. During that time, I had to replace the starter (about 12 hours for me), replace the valve cover gaskets (another 10 hours), and just now, clear the AC/cowel drains (3 hrs). These repairs are normal at this mileage.