Warming up

I have read that one needs to warm up a car for only 30 sec. yet my subaru has a cold water light that stays on or longer than 30 sec. Do I need to wait for the light to go out or do I need to wait only 30 sec.

No;the light tells you that the car has not reached operating temperature. The quickest way to warm up a car is to drive away GENTLY after the oil has had a chance to circulate to the valve gear, which takes about 30 seconds unless you are in Northern Alaska.

The light is tilling you not to hit the freeway and drive 60mph. How long you need before driving depends on the car and temperature. 30 Seconds is plenty for non-freeway/non-agressive driving. Take it easy (avoid fast accretion or high speeds until the light goes out.

Your car only needs 30 seconds.
If you choose to warm it up longer, because you like to get into a warm car, then warm it up as long as you wish. You’ll be doing no harm to the car.

Unless it’s extremely cold outside (say below zero) 30 seconds or so is all the engine needs before you can drive off. Just drive gently until the cold indicator light goes off. The engine will warm up more quickly if the car is driven than it will sitting still and idling, and the quicker it warms up the better it is for the engine.

If it’s extremely cold, wait 60 seconds.

Start your car
fasten you seat belt
check your mirrors
put on your sun glasses
Drive!

My life changed ever so much when I finally got a garage to put my car in. Most of my life I had to park in the driveway, and I tell you in the winter it is never safe to drive until you have visibility all the way around. Thirty seconds simply does not do it.

I tended to run the motor while I scraped windows. But, sometimes they simply had to defrost, and that burned a lot of gasoline.

I remember one major ice storm at work, We all had about half an inch of solid ice on all our windows. I don’t think I was able to drive for half an hour or longer. There was no way to scrape ice that thick.

Still, in non-frost conditions, I agree no long wait is needed.

Here is a recent Yahoo article on the subject. 30 seconds is often all you need to warm up your vehicle. When I lived in Fairbanks it was never more than a minute or so even at 40 below zero.

I m with Jos. Driving slowly is your best warm up, but if it s unsafe to do so, wait for the warm up light.

Why is that song ‘I wear my sunglasses at night’ coming to mind when I read this?

As soon as I start up, I place in Drive.
I let idle move the car towards my destination until I get to the STOP sign at the end of our street.
(In the same time another sits and idles in Neutral, I am down the street with engine warmer.)
If other vehicles approach from behind, I signal right and move right so they can pass.
After the STOP, I GENTLY accelerate attaining no more that 1,500 RPM up to the next STOP sign.
Under gentle load warms thengine sooner, keeps the idle speedown and USES the fuel rather than wastes it making needless pollution.

32F and above 30 secs is fine. -01F or below 5 mins is my choice.

Do you warm up in Drive, or let the engine freely spin in Park or Neutral?

My friend would get dressed and go out into the cold to start his engine, leaving his car illegally puffing. (Can’t wait for the police to catch and fine him. Hope no thief steals his car.)
Then back into the cold returning to his house, letting cold air in through his big front door, again.
Then go back out into the cold, (more cold air in his house) walking to his car, again.

I go outside ONCE, front door opened ONCE. Get in, start engine, drive away in idle.

It has been forbidden to use Yahoo as a source for information automotive related, didn’t you get the memo?

Our newest car has a digital engine temperature readout. If I start the car and immediately begin to back out of the garage, the temp gauge already reads 2 degrees F over the initial reading. Starting at 20 degrees F, after about a mile of 25 mph driving the temp gauge reads 100 F.

After about 1-1/2 more miles at 45 mph speeds, the temp gauge reads near the final range of 190 to 198 degrees F.

Keep in mind that the oil temp lags the engine coolant temp. I know this from changing oil at home.

I don’t know when it’s safe to use full throttle; seldom use full throttle anyhow but I don’t worry about driving normally after a very short time/distance unless the starting temp is extremely cold such as minus 10.

The cold water light is intended to discourage hard driving while the engine is cold. You can drive with the cold light on, you just shouldn’t drive hard with it on (no full-throttle acceleration or similar abusive tactics). This information should be in your owner’s manual.