CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Warming up a car or just drive it?

I know this question was covered many times before but here is a twist.
I have to take care of a friend house friends she is away.
The house is about 400 feet from a busy road with a speed limit 55 mph.
In this scenario you have to gun the engine as soon as you are on the highway. The 400 feet is not enough in my opinion to warm up the engine enough.
So would you idle it for a couple minutes or just drive it right at the speed limit?

I would idle for a short amount of time.

Of course you should. It’s common sense and you are right to think you should. ALL my tractors, outboards mowers and other internal combustion motors need some warm up depending upon the circumstances. Low speed driving dosen’t need much warm up, your senerio does. But, you are still not warming up other fluids that only do so while driving. So still, when you hit the highway, upset a few and gradually build up your speed for the transmission and differential and other warm up, again depending upon the temperature.

Thanks for the replies. I will try to find an alternate route maybe the opposite direction for a mile or so to give everything a chance to warm up…

In the very cold winter weather I’d give the car a few minutes to warm the motor, 2-3 and look for a spot to enter traffic where you don’t have to gun it on take off. In summer about the same, but not as worried about the need for a fast take off.

While I agree that 30 seconds of warmup has value, I don’t think you’ll be able find anyone here who can point to early engine failure and say it was caused by accelerating hard too soon after startup.

I’d let it warm up a little bit, even in summer. Not long: maybe 30 seconds or so. In winter I let it warm up a bit more but am not really sure what’s needed but I have to acclimate to sitting in that cold cabin on that frozen seat. It is more a shock to my system than the car’s, I suspect.
It isn’t so much the act of warming up but you want the oil to start sloshing around.
On my old VW bug, you do the opposite but for the same reason. The oil pump isn’t the most efficient so you want the oil pressure to build as quickly as possible.
You basically drive it like you stole it, seconds after you turn the ignition key.

In my opinion, hard acceleration is a bigger issue than having to drive 55 MPH right away. Can you wait a bit longer for a nice gap in traffic?

If this arrangement is only for a limited time, any extra wear from whatever you do probably won’t matter much in the long term.

I know two people who have (had) the habit of taking right off and accelerating hard, summer or winter.

One had a '76 Granada that was smoking before 50k miles. He changed his driving habit in his next car.

One has a '90 Accord, started trailing thin blue smoke until warmed up ~100k miles.
Now it’s over 200k and I still see him many weekday mornings racing off to work leaving a slightly thicker trail.
I don’t think it’s valve guide seals because it doesn’t smoke until he takes off.

Let it warm up a little but don’t go to the extreme. A former neighbor of mine used to “gun” his engine in the early morning hours to warm it up. It was hurting the engine but no amount of explanation was good enough for him. The engine finally locked up after a few weeks.

With well over a million miles driving carbureted cars and motorcycles and diesel tractors and trucks over the past 50+ years it is just second nature for me to leisurely warm an engine from a cold start before pushing it. Modern electronic engine control systems and synthetic oils make it less of an issue but at initial start up I prefer to sit and wait for the idle to stabilize to normal before shifting into gear and drive quite moderately until the temperature gauge begins to rise from the fully cold position. For any who have experienced driving a car from the 50s knows the notion of twisting the key and immediately driving away at a cold start was for day dreamers. And for some really fun starting look up a video of starting a John Deere diesel that used a pony motor.

In my situation where I have three miles of basically empty roads before hitting the highway, I start and go, no matter how cold, but I take it easy until I get to the highway. This has not hurt any of my vehicles, but in your friends case, I’d let it warm up a little. I kind of like the idea of pulling up to the highway and waiting for a big opening and then accelerating easy up to speed.

If a big opening doesn’t come in the first three minutes, then the car should be warmed up enough to gun and go.