Since I apparently cannot get enough of my profession, I spent an evening watching the wonderful set of videos on the subject of Bore Scoring. These were prepared by PCA on Youtube and were truly impressive. I’ve come across the subject of bore scoring over the years many times, but I think the series of videos posted by PCA are very thorough and offer truly practical advice on the subject. In particular, the advice offered regarding prevention of bore scoring struck a chord with me. After letting it all process for a few days it seemed like it should be the subject of this month’s article. But not necessarily for the reasons you may think.
It seems the old ways still apply to the new world, which is to say that it still makes sense to abide by them:
Rule 1: Don’t start your car and just let it idle, then shut it down throughout the winter months.
I always just accepted that this was a standard rule, like not walking with your shoes untied. The initial idea behind this (as I remember) had to do with minimizing dry starts in engines that have been sitting. As a kid growing up in the frozen north, it was standard practice to “fog down” everything with an engine entering storage season. From an outboard to a V8. The second part of this rule was not to start it until spring, and not until you pulled the plugs and brought the oil pressure up cranking it. It turns out that this rule is sound advice to avoid bore scoring. Dry starts are not your friend.
Rule 2: Stabilize your fuel
Nobody likes instability, especially in fuel. This again, was one of the old rules. When you put a car away for the winter, always put fuel stabilizer in it. It turns out that breaking this rule causes deposits in your injectors and fuel system, which can create injector leaks, which can cause bore scoring. Interesting.
Rule 3: Use higher viscosity oil
I vividly remember the few domestic cars we had when I was a kid. Somewhere along the way we were doing an oil change with my dad and he remarked at the oil viscosity. Apparently, the car called for a 5W-20 oil and he balked at it. In his opinion, an oil that thin in an engine was simply ridiculous. After muttering something about planned obsolescence we put 10W-40 in it. These days it’s not so uncommon to use a 5W-20 oil (I can’t even imagine what he would have thought of 0W-40). Since I’ve owned Porsche’s and Audi’s, I’ve always used 5W-50 in my own cars. Always seemed like a good balance. As a side note, it seems Porsche feels that way too as many of the Classic Porsches (read 996/986 era and others) now show 5W-50 as the correct oil instead of the old 0W-40. In the videos, they mention that engine life can be prolonged somewhat even when bore scoring exists by increasingthe viscosity of your oil – especially if the oil contains high levels of Molybdenum.
Rule 4: Sometimes you do have to go “off the range”
As anybody knows who has met me, I tout that Porsche knows what they are doing. I follow their maintenance schedules and recommend that Porsche owners do so as well. That said, sometimes there are advances that can be made.
One of them that made a lot of sense to me was the notion of changing oil at half of the recommended service interval. In most cases that would mean changing your oil at 6 months or 5,000 miles instead of the normal 12 months/ 10,000 miles. This is something I have always practiced, with excellent results. Just ask our 200,000 mile Cayenne.
Also, the mention of using injector cleaner periodically made sense as well. There was a time when everyone I knew would put a bottle of Techron or an injector cleaner of some kind in their fuel system – for maintenance purposes (it just seemed like the right thing to do). It seems that, and the use of top- tier gas, can make quite a difference.
I guess maybe the old song is right. Everything old is new again.