Been looking at 159 in replacement for my Mini Cooper S. Looking at the 2.2 and 3.2 petrol versions with some of the cars around the 90k. I have checked the buyers guide but unsure about anything I should look at as these cars hit the higher miles?
Im comfortable with doing work myself if needed.
I bought my 2.2 with 105k miles on the clock. The car hardly has signs of wear, nothing rattles, and everything works . The previous owner did mainly motorway miles, so wear and tear was minimal. I bought on condition and also knowing that I would only add around 8k miles per year at most. In the year and a half I have owned this car, I have changed two tyres and a bulb. I would recommend one without hesitation.
There isn't anything I would specifically check in a high mileage car that I wouldn't also check in one that had done 50k miles. The main things I checked for were evidence of regular servicing, any history of timing chain issues, the M32 gearbox issue, and the condition of the steering rack. The M32 gearbox is mainly an issue with the 1.9JTDM variant due to the additional torque of a diesel engine. It can occur with the 2.2 engine, but I would say this is less frequent. The steering rack can require replacement due to the wrong fluid being used at the factory. I believe green rather than red fluid should have been used. However, there are quite a few of us that still have the red fluid, and have not encountered steering rack issues. A quick search on this site yields tons of information on these issues.
The two major issues specific to the 2.2 engine are hesitation and the timing chain. There are plenty of 2.2s that have not suffered from the stretched timing chain issue, but probably few that do not suffer from hesitation. You get some 2.2 engines where the owner has had at least one change of timing chain, sometimes more. Others last for life. My mechanic told me not to bother with a change unless the error code came up. So far, it is on its original chain. The hesitation issue varies from mildly annoying to very annoying, and can cost upwards of £500 to fix, although I know Gus at Alfatune insists a new exhaust is also needed, and his reputation speaks for itself.
On the issue of 2.2 vs 3.2, I'd say it depends on your wallet. The 2.2 is thirsty (I got 32 mpg on a 400 mile roundtrip to London and town driving sees low to mid 20s mpg), but the 3.2 will probably see 18-25 mpg. My advice would be to drive a 2.2 and see if you get on with it before considering these issues. If you decide to buy one, then find examples for sale that are within your budget and check out the service histories, and any evidence of these common issues. FWIW, a reputable Alfa independent can inspect the car for £50-60 and give you a report. I don't think buying a 159 is different than buying any mainstream car. It's just about knowing what to look for and finding a well maintained example.