warming up my car

i've had many people tell me different things about warming up cars. First some people have stated that back in the days of carburators, warming up a car was crucial but that it is not needed for today's fuel injected cars. Then there are people who disagree saying that engine components, like belts and shit, still need to be warmed up. What are your thought on this?

The best way to warm up a car is to drive it---gently.

Agees with V-8Fan, but there is an exception - racing engines.

Racing engines should to be heaten up with an external heater before they are started, if they are started cold they can break. Using an external heater is also a good idea for standard engines.

Just don't try warming it up by letting it stand on idle, this will not get the engine very warm but the rich mixture will also "wash" the oil from the cylinderwalls .

Letting the engine warm up is still important, especially if you plan on getting the most miles possible out of an engine before it needs to be rebuilt.
Generally, I start the engine and let it idle for about 30-40 seconds and then drive gently until the temp guage is showing the "normal" operating temperature. This is probably the best way.
It's important even with fuel injection to do this, mainly to reduce engine wear, the warm up ensures that oil (those first 30 seconds) is everywhere it needs to be before you put the engine under load, and driving gently also reduces wear, but it's important because your engine operates inneficiently below it's normal operating temperature, so you waste less fuel and reduce wear on the cold engine by doing this.

The best way to warm up an engine is to start it, and punch the gas pedal to the floor, letting the tach hit the redline each time, until warm.:lol2: :lol:


I'm just playing, noone in their right mind should ever do that!:screwy: Like has been said, drive gently while cold. I don't like to rev mine past 2000rpm when cold.

thanks for the info

I always let my car warm up for about 10 minutes. It's no fun driving a Ferrari when it's cold.... :biggrin:

10 minutes!!....i don't have that kind of time in the morning......maybe if i had a ferrari i would...hahaha

i usually let my car stand on idle for 10 mins or so to warm it up when it's really cold out. Is this bad?

first i put the peddle all the way to the floor and press the brake all the way to the floor. Then i start the car and hold it for about 30seconds to a minute, then i let off the gas and shift into neutral. Then i floor it again for another 30-60 seconds. AFter that i drop it in drive and try and get the RPMS at redline for as long as possible. Once the engine is warmed up its ok to drive it slowly, it wont do any damage. This way i figure its best to teach the car that it needs to get warmed up quickly so that in later times i wont have to let it warm up for so long. Good luck and try my way!!

....Dear God I hope you're joking

Its always best to let your engine warm up some before you drive it, all of the lubricants and other fluids in teh engine are designed to work best when the engine is at normal temperature. Not saying they don't do their job on a cold engine, but they are optimized for normal operating temp.

Assuming -Jayson- was kidding, one of the worst things you can do is rev the engine before the oil has had a chance to circulate. as a car sits the oil tends to settle down out of the heads, leaving the cams/lifters/rockers/etc essentially without oil. any of these parts + no oil = no good. One way to combat this settling of the oil is to switch to synthetic oil. the major difference in synthetic oil is that the molecules are approximatly 1/10 the size of normal oil's. this allows the molecules to get 'stuck' in the microscopic blemishes in the oil galleries and other components.

sorry for the lengthy explanation, I probably coulda left some of that out....

what is my way a bad way or something? Only problem is the engine likes to break down alot now, stupid engine maybe next time i should use maple syrup for 10w-30... they look like the same thing. And also how come when i put Absolute vodka in my tank the car doesnt run as well? i mean its flamable shouldnt it burn just like gasoline? I even tried Popov because that stuff taste like gasoline and it still didnt help. Then a guy told me that the sugars and what else thats in liquor will wreck my engine, so i quickly got a bottle of paint thinner to get it out, hope it all works buti dont think it did cause now the engine wont start. So then i was like i need to jump it, so i took apart a wall socket in my garage and attached it to the battery cable, but all it did was spark for a few seconds and then the circuit breaker was tripped. Yyeah but im pretty cleaver around cars, i had an oil leak from that thingy with all the spark plug and junk, so i took some house hold super glue and filled in the leak, no more leak. I figure i saved myself a couple hundred dollars by doing it myself. Anways the tow truck is hear to pick up my car, so ill tell you the repair bills, normally i just start hitting the engine with a hammer to fix it, but this time i think i did some damage. Oh well. . .cars are so stupid.

i feel sorry for the poor sap who takes this advice :shakehead:

i think youve gotten your point across

The best way to start a cold engine is to use a pre-lube pump to pump oil thru the engine's passages before hitting the starter.

But since most people don't, I guess it's a moot point.

i usually let my car stand on idle for 10 mins or so to warm it up when it's really cold out. Is this bad?
This isn't very good for the engine. Not only takes it a long time for the engine to heat up, the engine will also run rich which washes of the oil from the cylinderwalls.

The best way is to preheat the oil and water or at least one of them and then start the engine. Otherwise the engine should be started, stand on idle for a little while so it can build up the oil pressure and then the car should be driven at low speed and low load until the engine gets hot. When the temperature rise we can use more load and higher engine speeds. Full load shouldn't be given until the oil has reached 70 degC.

When an engine is cold many of it's part hasn't the right shape and/or dimensions and the oil is also thick and has problems to lubricate in small passages.

saabjohan- very good post, props to you

Jayson- You're method is great, especially if you'd like to watch pistons 1, 3, and 6 fly through your hood...

Two reasons for driving off without using too much power during freezing temperatures:

1. Cold oil doesn't circulate well. It's possible to lose sufficient lubrication to the rod and main bearing journals if you go to high power/high RPM before the oil has warmed up at least a little bit. The oil can be thrown-off the rod journals faster than the thick cold oil can flow to the bearings.

2. With a very cold engine in freezing climates, if you were to do a high speed/high power output acceleration immediately upon starting your engine, the pistons would heat-up faster than the engine block and expand to the point of rubbing the cylinder walls. Do that often enough, what happens is that the cylinder walls become skuffed by the piston skirts which in turn destroys the piston rings. This condition is known as "seized pistons." The cylinder walls have a scraped look and so do the piston skirts. If you're planning to pull a heavy trailer, or are driving a heavy truck, allow the engine to warm-up to where the temperature gauge is at least beginning to show an increase in temperature before driving off, and then drive away using very little power to allow the engine to warm-up faster.

Anyone who has experience "seized pistons" will tell you that they first experience a loss of power and simutaneously noticed that the engine was throwing oil. It was throwing oil because the blow-by around the piston rings created excessively high crankcase pressure. The oil temperature and thus the engine coolant temperature becomes very high. That's because the heat of combustion was blowing around the rings and blowtorching the oil in the crankcase too.

In the average new gasoline engine, the average piston skirt to cylinder wall clearance is about .0015 to .0025"... .004 to .008 for the big diesels, and .008 to .012 for airplane engine cylinders. I know...I've rebored hundreds of 'em. Also reground LOTS of crankshafts. It doesn't take much to cause that piston to expand the one and a half thousands if the engine block is still at freezing temperature and you've got the throttle pedal on the floor. Once the engine begins to warm, the cylinders also expand and maintain the proper clearance. Simply start your engine, allow a few seconds for the oil pressure to build up, and then drive away using very little power without lugging the engine. It will heat up faster that way. Don't lug it, but don't overspeed it either. Within a few minutes the temperature will rise, assuming that your thermostat is functioning. At that point you can just about do anything with the power output and not hurt your engine. Only then should you put a hard load on the engine if you have to.

I've said it over 100 times, drive the engine nice until it hits operating temp, then you can drive it hard all you want. (Well, not ALL the time, but you get the point!)

Excellent post btw Doug, I'm glad some people care enough to give a long, thought out post like yours!

Assuming -Jayson- was kidding, one of the worst things you can do is rev the engine before the oil has had a chance to circulate. as a car sits the oil tends to settle down out of the heads, leaving the cams/lifters/rockers/etc essentially without oil. any of these parts + no oil = no good.

It is good to rev the engine to 1500rpm when it starts. Most cars do this automatically. The reason is that the cylinder walls and the camshaft (in pushrod engines) get a lot of their lubrication from the oil thrown off the crankshaft. The engine has to be at 1200+ rpm in order to get good splash lubrication. I hold the rpms at about 1500 for several seconds after starting the car. Obviously you shouldn't rev it above 2000rpm either because that puts unneeded stress on the engine. But all in all if the engine is well made and you maintain it, it will outlast the car.
My 86 Volvo 740 Turbo has 190,000 miles on it (lots of city miles too) and it still runs very strong. Turbo motors put a lot more stress on the oil and the engine. It has had conventional oil all its life and it still runs fine. It has a little piston slap when it is cold, but the car is on its last legs so I don't really care. It wasn't warmed up for more than a few seconds for its whole life so I don't think it is worthwhile to waste gas in order to warm up the engine so it will last longer.


FYI it never snows here so it might be different if you live someplace extremely cold.