In the garage we keep themergencyehicle hood covered with a sheet draped down over the front and electric skillet turned on to warm thentirengine compartment.
At least the person being interviewed didn’t spread what I think is false information. He talked mostly about electric vehicle issues.
This article is the source that the news site used: Does Warming Up Your Car Actually Help? | Warming Up A Car Myths
I guess the idea is that driving the car immediately causes it to warm up more quickly, reducing the amount of time that it has to run very cold. As usual, they say that increased pollution is the reason to not warm up a car.
The only way I see how idling the car could cause damage is if it is too cold to let the oil settle back down in the oil pan, causing loss of oil pressure. Getting it to warm up faster would somehow prevent this, but that seems far fetched. Better to shut it off after 30 seconds and then start it up again a few minutes later.
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Well I’m calling bunk that the oil drains from the pistons when it is not moving the car. That makes zero sense.
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Does anything RG posts ever make sense ? The answer is No .
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This sounds to me like a load of bullplop. Whether you’re warming up the car in your driveway, or whether you just get in and start driving, either way, the engine is started from cold, and thermal cycling will occur.
The only real risk from thermal cycling is that composite head gaskets will wear out after a certain number of thermal cycles, and depending on the materials used, last for about 100,000 to 150,000 miles. Aftermarket gaskets are redesigned with better materials to extend this life further (assuming proper installation and surface prep).
That was the sources in the article. But IMHO, if oil pressure is normal, parts are lubricated. I want a car sufficiently warmed to keep the windshield free from fogging over.
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Just showing what is outhere.
As a teen tree-hugger and Greenie, I would starthengine and allow idle to move the car to the stop sign. Then gently accelerate.
"Gas-powered cars need oil to keep their engines lubricated. When you start a car, an oil pump circulates the oil in less than a minute. But if you let your car idle to warm up the cabin, the oil can get stripped away. "
So are we to believer that the oil pump just suddenly stops working after that initial minute or something?
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Yup!
The premise on which the OP bases his belief is truly illogical.
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Maybe the theory is that if the car is rev’ing low rpm (idle), the oil pump doens’t spin as fast, so not enough oil gets to the piston rings. Guessing problem w/that theory is that at low rpm not as much oil is needed. The premise seems unlikely. Frequent idling could eventually could cause engine coke and oil deposits to build up I suppose.
Oil pumps are designed to provide enough oil at ANY condition. All the needs at idle are supplied. Nothing is left “dry”. So much oil flow that the pressure relief valve opens and excess flow is dumped back to the pan even at idle. As the engine revs faster, even more is dumped overboard but the engine is always supplied adequate oil.
Modern engines have designed variable pumps to reduce the HP required so that less power is wasted just dumping the excess back to the pan.
The rings don’t need much lubrication which is why they are generally splash lubricated. Same for piston pins. Bearings are pressure fed. It isn’t rings you need worry about…it is the bearings.
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While the conclusion, “experts say driving after 30 seconds to a minute after starting your car is a best practice” is true, much of the narrative is hogwash.
Pre 1980’s cars used a “choke” to increase the fuel mixture which could be set either manually or automatically (press accelerator foot to the floor) for cold weather starts, usually for 30 seconds to a minute. By which time the automatic choke would release or the manual choke would begin demonstrating the classic “rich fuel misfire”. (Picture your lawnmower or snowblower running on choke).
“Constantly letting a cold engine idle can actually be counterproductive because it gradually strips oil away from the engine’s pistons and cylinders.”. Pistons and cylinders are generally lubricated from below using the “splash method” so assuming you’re not running 90 weight oil in your crankcase, it’s hard to imagine how you wouldn’t have sufficient splash lubrication within less than a minute.
“Top end lubrication” for thicker oils driven by the oil pump may conceptually be a problem but today’s motor oils range as low as 0W-50 with 0 being the lowest Winter viscosity.
For modern cars, use the manufacturer’s recommended motor oil, give it a minute to warm up while you clear the windows, avoid drag racing you neighbor’s kid to the end of the block and you’ll be fine.
For older cars running 20W- 40, set the choke, bang on the dashboard, carbs, free the brakes, mutter the ususal prayer and go for it. My 1952 has had the carb’s replaced (shaft wear) and lower main bearings (had an extra set sitting around) and sitll runs fine.
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You know that it pumps regardless of engine rpm.
Easier on thengine if RPMs are lower as engine is warming up. Under load idle allows earlier warm up which be.tter and moreven.
Well, here in northern LA county, last week I had a bad windshield frost from the cold. Problem is we are not used to having ice scrapers any more. So, I did warm up the car/engine for a few minutes until I could see where I am going. Maybe I shortened the engine’s life, but definitely prolonged my life and our neighbors’ lives.
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With the morning frost buildup here, I am finding myself having to use the Remote Warm-Up Apparatus to defrost the windows so I can safely see where I am going. My Remote Warm-Up Apparatus consists of an extra key on a keychain by itself; since my car has no power door locks and no security system, I can start the engine and lock the door to deter anyone from hopping in and driving away.
False security . The vehicle with actual remote start with shut the vehicle off when a door is opened . Yours will keep running even after they break a window and reach in to open door . Then they just get in a nd drive away.
Once they step on the brake to put into drive the engine will shut off.
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The ONLY way it’s hurting the longevity of the engine is the fact you’re putting engine use on the vehicle, but no mileage. So the engine is a little worn out more than a vehicle with the same mileage that doesn’t idle. The rest of the article is total do-do.
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Totally agree with bchoen and mikefromNH. The only way you can reduce your car life from reasonably warming up your engine is to drive into a semi that you didn’t see because of frosted windows.
With the manufacturer’s specified oil, changes at specified intervals and manufacturer’s scheduled maintenance, pretty much every car will last well beyond when you’re tired of it and/or rust/corrosion/plastic degradation has resigned it to the scrapyard.
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Ours will keep running even after you open the door. You have to shut the ignition off, then restart it if the 10 minute timer has not elapsed. I have not tried but imagine putting it in drive is disabled.