To run or run?

[Lewis07]

On a train home on a Friday evening so excuse the deluge of questions. But, do you guys suggest warming these large engined beasts at idle, or on the hoof? I have been advised not to let them idle too long from cold and to jump in and get going but to keep the revs down at first. Grateful for your views.

[jamiep]

I was told by an engine builder to never let a car warm up on idle, just drive it slowly till the oil temp gets up.

[Bonnie and Clyde]

I think you have to keep it at about 3500 revs until the engine is at temperature.
The warning alarm sounds if i go over that tellin me to go up a gear

[Lewis07]

I think you have same model as me but I haven't heard a warning sound so guess I'm keep the revs below 3500...

[petrolzed]

Drive it gently, mine takes about 4 to 5 miles of open road to fully warm up from cold.
During that time it has drank a fair bit of petrol.
Not a car for traffic jams or short journeys!

[300bhp/ton]

It's a modern engine and design to survive daily duties in a truck. Just do't drive like an idiot until its warmed up and it'll be fine no matter how you bring it up to temp.

[Bonnie and Clyde]

Does anyone else get the change up gear sign on the disply along with a warning tone. It kicks in at 3500 rpm

[pa07 bat]

Warning at 4000 rpm on VXR if engine not up to temp.

[Gas_Man]

No warning on mine

[ads_green]

I generally don't use more than third throttle, keep under 3k rpm and importantly don't let the engine struggle/labour in too high a gear.
Oil temp is considerably more important that water temp and can take a good ten minutes to get up to operating levels.

As far as I'm aware, the main reason for not warming a car at idle is down to emissions. It takes considerably longer for the cat to reach operating temperature (and I guess everything else too) before it starts to do stuff.
This is part of euro 4 engine standards in that it must reach emmission standards within a given amount of time - an easy way to help this is to state the car should be driven rather than idled.

[V2RAC]

This info about not letting the engine warm up whilst idling was fairly common knowledge in the days before cats were fitted.

[Lewis07]

[Bonnie and Clyde]

Lewis07 said:

We still don't appear to have a difinitive answer.

Would you like to add to elaborate

[Lewis07]

To idle warm up or on the hoof?

[Bonnie and Clyde]

Sorry i ment the comment before my last one. There was nothing there. I was being sarcky. Please forgive me

[Lewis07]

Sorry, can't keep up!

[ads_green]

Regardless of the reasoning, I think it's pretty much safe to say don't warm up on idle

[ringram]

Also whats the point warming the engine up but not the rear axle and transmission, then hammer it out of the driveway and give death to the rest of the cold driveline!?

[tim the pool man]

Bonnie and Clyde said:

Sorry i ment the comment before my last one. There was nothing there. I was being sarcky. Please forgive me

Weird, it's there when you quote it, but invisible in the thread...

[Paul--C]

Lewis07 said:

To idle warm up or on the hoof?

With any normally aspirated engine it is best to drive off immediately and warm up gently to oil operating temperature before accelerating hard. Approx 3 miles for up to 2 litre engines, up to 8 miles for over 2 litres and big V8s etc. This minimises engine wear.

For turbo or Supercharged engines, allow to tick over for at least one minute before driving off, (and 2 to 3 mins before switching engine off after driving), and warm up as above. This allows oil to circulate around Turbo / supercharger bearings and avoid expensive breakages which far outweigh the costs of any engine wear associated with not driving off immediately.