I am in the market for a 997.2 or 991 and I would like to know what to watch out for in cars that are 5-9 years old with very low mileage. A 2013 911 (any model\trim) with 15,000-20,000 miles sounds like an almost new car but I am aware that a car that has been sitting for many months without being driven can present its own challenges. Obviously, not all low mileage cars are the same, as a car that has been driven 3,000 miles per year is likely a safer bet than one that has seen 10,000 in one year and then 5,000 miles over the other 5 years. Is there a general school of thought with respect to how to approach very low mileage 911's that are at least 5 years old?

 

I don't think a 20k mile 991 is super low mileage, since these cars are second cars for most people and when combining that with winter weather, many will see limited use per year.

However, I would mostly want to be sure that maintenance was still completed both on time or mileage. For instance, the spark plugs probably do not need to be replaced based on mileage, but they should be done every 4 years based on time.

 

I’m that guy. I have a 2012 911 Cabrio in conjunction with my other car and my 7 mile round trip to the office, and living in Michigan (store the 911 during the winter) I drive about 3,000 miles per year. I just turned 24,000 miles, Hand car washes only and try not to drive it in the rain. I have the oil changed every year and do the other required maintenance based on years not miles. Just completed the 40,000 mile maintenance this year . I think this is the kind of car you should be looking for. These cars are tanks but I would rather find a gently driven one if I was in the market for one.

 

12K mile 2012.5 here. Oil Change once a year; albeit sometimes just to cars and coffee but engine comes up to temp and everything cycles at least a couple times. Spark plugs were done at 6 years and showed no evidence of actually needing to be replaced. Driven at least once a month and it's one of 4 cars in the family. Always hand washed. Full PPF + Ceramic. It's in better condition than 99% of the brand new with delivery miles.

 

2012.5 here. My car is perfect. I drive it every 2 or 3 weeks. It is maintained on the yearly porsche maitenace schedule to maintain the warranty.

 

2012.5 991 S Cab also...purchased in August with 13.4K. Lived all of its life in south Florida. Annual service performed at local P-dealer but no other service. Still on the original battery and not driven in weather. What's not to like??? I will sort the "recommended" services out in the next few months.

 

search on the 997 board for scored cylinders and take to heart every piece of advice from LN Engineering. Ultimately DFI engines need a specific oil which Porsche does not use which is better at inhibiting moisture which leads to scoring. So the more often you change non-DFI specific oil the better. Annual or better ideally. LN recommends Driven oil only for DFI motors. 997s are now at the age that scoring is showing up in fairly large numbers.

 

The LN recommended oil for DFI engines is to prevent low-speed preignition (LSPI) not bore scoring, it has a different additive mix to help limit detonation. Maybe there's a relationship between LSPI and bore scoring but I've never seen it and I've never heard LN or anyone else claim there is. There is no evidence moisture causes bore scoring. There is some conjecture it's caused by leaking fuel injectors washing away the oil film but this has never been proven. Fuel dilution of the oil can be an issue with lightly driven cars but this is a concern regardless of oil type. Last off, the 997.1 is showing up with bore scoring but the 997.2 (9A1 engine shared with the 991.1) largely is not. There have been a small number of scored 9A1's but nothing like the prior M96/97 engines. Porsche made significant changes to the 9A1 aimed directly as bore scoring that appear to have been successful. People have been saying for years it's just a matter of time but it hasn't happened yet.

Bottom line, don't lug your engine, it causes high piston side force and can also lead to LSPI. Get your oil up to temp as often as you can, this will help boil off fuel dilution of the oil. Change the oil every 5000 miles or six months, particularly if used oil testing shows a high percentage of fuel dilution. Don't get on the throttle hard until the engine oil is at temp, this will ensure even piston/cylinder expansion and help maintain uniform clearances under load. All are simple, common sense steps that frankly apply to any engine.

 

^^ Yes, fuel dilution. Thanks for the clarification. LN has recommendations for both the 997.1 and .2 I just don’t have time to search for them at the moment. But they both are having enough failures that I wouldn’t want another one unless it was something less common like the Speedster.

 

15,000 miles isn't low mileage in my mind, 1,500 miles would be. A 2008 911 Turbo came up for sale recently in this area with 8,500 miles on it from new. And there's a 996 Turbo currently available with only 11,800 miles. My local dealership recently sold a 2018 911 Turbo S with 160 miles on the ODO. Owner bought it, ended up working in Europe for two years and parked the car the entire time. For the original owner, it's typically a second or third car, low mileage is pretty typical. And, you have to imagine that - unless they're fully retired - they probably have a pretty demanding career and not a lot of spare time to drive constantly.

 

As some have said, these cars are typically not DDs so you’ll see many used ones that have an average of <5k miles per year. My 911 is a toy and I drive it as much as I want, about 5k miles a year so far. I bought mine to drive and enjoy but more often than not, there are folks who prefer to worship them. Hail to the garage queen! I personally think that great majority of 911 owners do a great job of maintaining their cars. If you find one you like, a PPI is highly recommended.

 

No problem my friend. I've always thought it kind of odd that the forums are divided by models (997, 991, etc.) when the change in engines/transmissions has been happening mid-cycle and is arguably more definitive. There's a huge difference between the 997.1 and 997.2 powertrain, also between the 991.1 and 991.2.

Disagree with your characterization of the 9A1 (997.2 and 991.1) as having issues as the 9A1 powerplant has been remarkably free of problems and much more robust than the M96/97 engine of the 997.1 and 996. I guess it all depends on perspective though, none of these high performance engines will ever have the reliability of something like an indestructible Toyota 20R. I had two of those when I was young and stupid and don't think I changed the oil for two years at a time. Still it ran nearly forever.

 

I'd watch out for that big grin from your face once you land a 991.1

I'm a high miler and my 13 C4S has been pretty trouble free. Just ticked over 120,000 Miles.

 

I would consider 2000 - 4000 miles per year to be pretty normal for these cars and you aren't going to find anything that warrants special concern. The 991.1 has the same 9A1 engine as the 997.2, so if there is a risk of bore scoring it still exists.

 

I think you'd probably be defined as "Porsche's Beta tester"; you'll encounter problems or defects years ahead of the rest of us!