For winter storage up north, some people shut the engine down and leave it that way until Spring. Some will start the engine occasionally for a few minutes, and that is generally considered poor practice because it may promote water, acids, and fuel accumulating in the oil.

I've always used a different schedule if we don't take the car South for the winter- during the winter I start the engine twice a month and exercise every switch and control in the cockpit (lots of 'em!), and make several runs up and down our150' driveway. Use as many gears as possible, brakes/ABS, steering full lock, etc. until the oil gets up to 175'. Then shut down for another two weeks.

Since I do an oil analysis with each oil change, I now have about 10 years of experience showing that the first analysis after my winter storage produces results similar to a summer-only run on the oil of 5k-7k miles. This year I did the Fall oil change and drove it only 165 miles before storage, ran it 8 times as mentioned above during storage, then sent in a sample before any additional driving. The results:

JAMES: Thanks for letting us know about the short trips and the cold weather. From what we can see, your
engine wasn't bothered at all. Metals are sitting at some of their lowest levels on the page, which is great
since this oil's only been in place for 167 miles. This oil doesn't need to be changed out yet. Feel free to
keep it in place for another 4K - 6K miles as usual. The viscosity tested low again, but it's still not a concern,
especially since it's not because of fuel dilution. No coolant, moisture, or excess dirt was found, either.
Looks good from where we sit.

The low viscosity they mentioned shows up every time on the 0W-40, but it's still significantly stronger than 5W-30 so I'm happy with it.

Just another data point...

 

Oil with 165 miles on it that has been started and run up to operating temperature a handful of times looks clean? Stop the presses!

For the vast, vast majority of people, your procedure is untenable and opting to simply let the car sit is a perfectly adequate substitution punching in at far less effort.

 

If your procedure works for you, great. I will continue to just let the car sit unstarted during storage - that has worked well for me for many years.

 

Unless you are going to start car and drive it, better to just leave it. Just idling will just introduce moisture in places you don't want. Allowing the engine to run for at least 10 minutes once a week gets it to normal operating temperature. Apart from recharging the battery, you won’t accomplish anything else. Consider driving around your neighborhood to wake up the power steering, transmission, suspension, and braking systems. Typically, these crucial systems go on a snooze when your car lies idle. Therefore, a few minutes of driving will help bring them up to speed.

 

Where?

 

I live in South dakota, where it is always cold and snowy in the winter. I usually put my vette away for the winter in late November or early December.. I clean it, put the battery tender on it, throw on the cover, and leave it, unstarted until late March or early April, until spring is finally here. I have been doing this for many years, and I have never had a problem when its finally time to get the car out again. I see no need to start it.

 

Exhaust. Need higher revs and heat to burn it off.

 

For me very simple hook up the battery tender and let it sit until Spring.

 

Back when the C4s were being built the factory had a Corvette Action Center that Customers could call for questions about their car. Gordon Killebrew (https://www.corvettemuseum.org/gordon-killebrew/ ) was one of the GM employees that used to work the phones at the center and I got him when I called about how to best store my 1986. The first thing he said was, GM doesn't design or build the cars to sit around. That isn't one of their design criteria. The best way to store a car is to drive it. Driving it keeps moisture out of the exhaust, heat from driving evaporates moisture and spreads lubricants around the transmission and differential gears to reduce corrosion of the gears, transmission seals are lubricated which increases their durability, etc, etc.

Bill

 

Water boils off at 212 degrees or so. Idling up to temp will easily get your exhaust system hot enough to boil off any moisture accumulated from being parked in a garage for a week or two since the last time you started it and idled up to temp.

 

True. But idling will take a while to heat up the NPP.

 

Gixxerman is right!
I am a private pilot and also an airplane owner.
Same advice was given to those of us who are plane owners by the airplane mechanics.
We've been told simply don't do it. If Oil Temp is not reaching the normal operation temp levels and if the engine is not running at normal cruising RPMs that kind of action actually harms the engine instead of doing any good.
Just simply leaving the airplane in the hangar untouched for a few months was better than starting once in a while and idling around the taxiway at walking speed then put back in the hangar again.

That condensation issue is a real concern.

I am not an auto or airplane mechanic by all means or even a car enthusiast with any level of knowledge. So, I am just relaying what I've been told.

 

I "baby sat" my son's C4 on one of his 1 year tours in the sandbox, I inflated the tires just below max air presure, hooked up the Battery Tender Plus and left it alone the whole time. When he came home to pick it up, it fired right up with no issues.

 

Your storage puts unnecessary stress on the car and nothing else. If you can't actually drive it, don't even start it.

 

As above --- just on tender and off till spring when ai can drive it at a regular pace for needed errands and to bring ALL parts up to running temps.
Just me after 40 years of car storage -I M O

 

Quite right. Many of us remember cars of the 50's and 60's which had mild steel exhaust systems that would rust out every 3 years or so. Here is my relevant experience. I had an old Aston Martin that needed a new exhaust system. I had a local shop fabricate it from the aforementioned mild steel. This was a collector car that was driven once or twice per month, and never in the winter salt. I never put it away with less than 30 minutes of continuous driving to get things hot. (And with a 14 quart oil sump, that took a while.) When I sold the car 22 years later those pipes and mufflers were still good.

 

No truer words spoken can be deemed more important.

 

I am your neighbor in Iowa, experience the same type of weather conditions you do, and have always stored my car exactly as you describe.

My thought relative to starting or not starting was always focused and centered around the answer to this question: what is the worst possible set of conditions that you can possibly expose your engine to over time? The answer that I came up with was a series of repeated short duration cold starts over time conducted under extreme cold weather conditions. It is worth noting that for each cold start, all engine internals have been stationary for a substantial time and have only a very thin residual coat of lubricant from the last startup that is expected to instantly protect all critical contact surfaces immediately upon startup while definitely not at normal recommended lubrication temperature, zero flow and zero supply pressure. After each engine shutdown, the engine acts as a magnet for moisture concentration and condensation.

Why subject the engine to this scenario on a repeated basis when starting serves no purpose and can introduce potential harm to mated surfaces? Cumulative effect could be a problem --- this is a study for a specialist in tribology for sure.

 

I believe we tend to 'overthink' things when we try to best maintain items that we are very fond of.

 

Where I live we have wimp winters, but a snowfall or three...I leave the car in the garage and leave it on the tender unless the roads are clean and dry. I then will take it out once a month and drive it for about an hour. Then back it goes. One thing I do for that first start is hold the gas to the floor and crank for about 10 sec or so to get the oil pressure up a bit without the engine firing. I then start normally.