erring on the side of caution / better being safe than sorry, yadda yadda.

usually start it let it run for a minute then drive carfull to operating temp.

From the RAA

Question 4

What is the best way to warm up a cold engine in a modern car?

Manufacturers in general do not recommend any prolonged idling as a means to warm the engine up. A cold engine uses more fuel than a warm engine.

It is not necessary to warm up a cold engine by letting it idle. Once the engine idle speed has stabilised, which should occur within a few seconds of starting, select the correct gear and proceed to drive the vehicle. The engine will warm up faster while driving rather than idling.

"More proof but no doubt some you guys know better"
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Warm up the car by idling

We can all pick up bad habits driving. But, like Dr Karl, it seems some of us are guilty of a bad habit before we've even pulled out from the curb!

By Karl S. Kruszelnicki

We can all pick up bad habits driving. But, like Dr Karl, it seems some of us are guilty of a bad habit before we've even pulled out from the curb!

I've had a lot of fun teaching the Junior Members of my Family how to drive the Family Chariot. But along the way, I realised that something I had done for a long time was actually wrong. Previously, I tried to be "kind" to my car's engine by giving it a nice long idle before I pulled away from the kerb. But when I went looking, I found that long idle was actually harming the engine, and the environment, and my wallet.

The powertrain of a car is the mechanical stuff that makes it go. The power starts at the engine, goes through the gearbox and finishes at the driving wheels. Les Ryder, the chief powertrain engineer from Ford, USA, said in the January 2007 issue of Popular Mechanics, "Engines run best at their design temperature". In other words, Mr. Ryder is telling us that engines run most cleanly and efficiently somewhere between 85°C and 95°C. Idling is not the best or quickest way to warm up your engine. Gentle driving is.

The Canadian Office of Energy Efficiency agrees that the best way to warm up your engine is to drive it. Even if the outside temperature is -20°C, they recommend that you idle the engine for only 15-30 seconds before you pull out onto the road. You need even less idling time at the temperatures we usually experience in Australia.

Idling an engine is bad in so many ways. The fuel is not completely burnt, so it condenses in drops on the cylinder walls. This leads to both extra wear of the cylinder walls (because the fuel washes the lubricating oil off the walls), and unburnt fuel flowing down the walls and contaminating the oil in the sump. Idling also drops the temperature of the spark plugs, leading to dirty plugs, which can worsen your fuel consumption by some 5%.

You might have noticed a vapour coming out of the exhaust of some cars in the early morning. That vapour is not the oil vapour of a worn engine, but the normal water vapour from a cold engine. So the longer you idle the engine, the longer it will take to warm up, and so more water droplets will be deposited inside your exhaust system – making it rust sooner.

A long time of idling means that the engine will produce a lot more unwanted pollutants. For example, modern cars have catalytic converters. When they get to their normal operating temperature (400-800°C, which is a lot hotter than the engine), they convert nasty pollutants into much less nasty chemicals. And you guessed it, the quickest way for catalytic converters to get to their normal operating temperature is by driving, not idling. The longer the time that you idle your engine, the longer that your catalytic converter is too cold to do its job.

Canada has started a national campaign to reduce unnecessary idling of engines. There are similar regional campaigns in Japan and the UK, and in the USA, 13 states have now passed laws regulating idling of engines. The ski resort town of Aspen, in Colorado, has passed laws making it illegal for car engines to idle for more than 5 minutes.

People are now talking about the benefits of switching off your engine in traffic, if you are going to be stopped for more than 10 seconds. But this is exactly opposite to the Remote Start function, available in some US cars, which lets you start the engine from some 60 metres away. The advantage is that you walk out of your house into a nice warm car. The disadvantage is that in 10 minutes of idling, you burn about half-a-litre of fuel.

The Canadian Office of Energy Efficiency crunched the numbers for the hypothetical situation of each Canadian driver idling their engine for 5 minutes fewer each day. Over a year, that reduced idling would save Canadian drivers C$646 million, and stop 1.6 million tonnes of greenhouse gases from escaping into the atmosphere.

When you idle a car, you get zero miles per gallon, lots of pollution, and a hole in your wallet.

Published 07 February 2008

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Beaten up old 98 Gen 2 Liberty, 13.0, stock V3 STI running gear.
07 Transit motor home
69 VF & 70 VG Valiants needing full restoration
Yamaha Zooma 50cc rocket hopefully going with the Transit.

I cant tell if its warm or not by the way she drives... When its cold, the gears are notchy, engine sounds roughish, acceleration isn't smooth. generally has a bad feel to it. as soon as thats gone, I flog it.

Im lucky in the way that i have a tricky driveway. - start her up, select cd, put it in reverse but only let clutch out enough to get it rolling, down steep driveway in neutral - with brakes on getting a bit of heat there too, 3 point turn to get her facing straight, all movement done with no accelerator, just a wee bit of clutch out at idle. down 20m driveway, and its almost up to temp already.

then just 5 more minutes of easy driving until temp is up, and it feels good again.

only time I let it idle is when it hasn't been driven in a while. I figure if its left for a couple of weeks, the oil could have drained completly from certain areas and it could take a while to fully lubricate everything properly. - This is by no means accurate, just my theory. more worried about too little oil than the temp of it.

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Twin scroll Pig Bi-Squeeling

I simply start car, wait about 30 seconds so the oil can reach all the important places in the engine, then drive... Nothing over 3k until car is warm and clutch feels good.

During that 30 or so seconds i usually give the brake pedal a few pumps to wake the brake booster up.

Pimpreza: nice find... interesting.

Interesting read...I leave it idiling for about 3-5 mins...till the temp is moving up to normal operating position...while below normal position I dont go above 2k...

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...He said Smooth Bee the skins is fat
I don't beg cause I'm not in begonia
I dress warm so that I won't catch pneumonia
My rhymes are stronger than ammonia
I'm a diamond, you're a cubic zirconia

I smell a bit of bullshit. either way, remind me to never buy a car of you.

To those who keep it low revs. agent orange inparticular - Under 2000rpm? does it actually move at those kinda engine speeds? Even when its warm you would think it'll be struggling and putting more wear on the engine underrevving it?

evn with my 2.5 it grunts and groans whenever its under 1800...

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Twin scroll Pig Bi-Squeeling

Mine doesn't go over 2500rpm when its cold, and it doesn't mind at all.

In fact with my car, if you attempt to pull away from 1000rpm, as long as you're in the right gear (not in a ridiculously tall gear), it'll do it with no complaint and to top it off, I have cams.

All in the tune

Yeah true true Joe...with the 6 speed I can do 70 in 6th at 2000rpm...good enough for most streets around my house. I have no probs keeping it under/at 2k till it's warm, meatbag! That's surprising what you sat about the 2.5...thought it would have been a little better than our 2lt's...

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...He said Smooth Bee the skins is fat
I don't beg cause I'm not in begonia
I dress warm so that I won't catch pneumonia
My rhymes are stronger than ammonia
I'm a diamond, you're a cubic zirconia