Q: If it is unnecessary to warm up a car in frigid winter weather before you drive away these days, does it harm the car if you want to warm it up for comfort? I have Reynaud’s disease that’s aggravated in cold weather, so I warm up the car when the temperature is in the single digits. I’ve read that “Idling your car in the cold not only wastes fuel, but it’s also stripping oil from critical components that help your engine run, namely the cylinders and pistons. When it’s cold outside, gasoline is less likely to evaporate. Your car compensates for this initially by adding more gasoline to the air-vapor mixture … and that’s where the problem begins.”
— D.M., Calumet City
A: In the olden days, when engines were equipped with carburetors, cylinder wash-down was more of an issue than it is today due to fuel injection. Yes, the engine must run a bit when first started, but the computer receives information about engine temperature and, as it warms up, the fuel mixture is leaned out. However, the part about wasting gas still holds true. We feel your pain, as we suffer from mild Raynaud’s syndrome. Fortunately, the fingers do not get too tingly to type.
Q: I got it when you said that most engine wear occurs during the first 10 minutes of driving. Long ago, we tossed SAE 30 Valvoline into a modified flathead V-8, but what about today’s multiweight oil? Does it really take as long for cold 5W or 10W oil to reach important parts as warm 20W or 30W oil? I’d be more concerned about the exhaust not reaching operating temps than the engine, in this situation. Enjoy your column … one of the best!
— W.L., Allentown, Pa.
A: Your reference to the exhaust reaching operating temperatures alludes to the need to get the catalytic converters lit off to begin controlling emissions. Yes, that is important. Getting the engine warmed up quickly is important. That is why the transmission will not shift into overdrive when cold. As to the low viscosity oils reaching their destinations quicker, you are correct, but other factors such as thermal expansion of metals is also a factor. And we enjoy our readers. They’re the best.
Q: Have you ever heard of this? My son has a 2013 Cadillac and has been experiencing loss of tire pressure that lights up the tire monitor. When he brought it to one of the local chain tire dealers they told him that there was corrosion on the rims that was preventing the tire bead from sealing properly. The car has 43,000 miles and is garage kept in the Chicago area. He was assured there was nothing penetrating any of the tires.
— R.M., Chicago
A: Heard of it? Mrs. Motormouth had this exact problem with her GM car. After a couple of years of sanding the corrosion from the bead seats on the rims, and then applying bead sealer before inflating the tires only to have them go low on a monthly basis, we found a solution. We bought new rims. Salt and other chemicals on the road cause the corrosion. That is why many motorists mount their winter tires on steel rims and store their alloy rims until spring.
Send questions along with name and town to Motormouth, Rides, baiduhai, 435 N. Michigan Ave., Fifth Floor, Chicago, IL 60611 or [email protected].