To warm or not to warm?

[BillyW124]

Guys, whats the deal here...

Drive off straight away or warm the engine up??

I always warm my engine up at least for 5-10 mins

views and opinions please.

 

[renault12ts]

Drive off straight away. As recommended in Mercedes handbook.

Diesels are very thermally efficient and so little heating up will happen on the driveway.

 

[BillyW124]

Have a w211 320 CDI and does take an absolute age to warm up.

The other is a c124 and always warm this up as my thinking would be obvioulsy to warm the engine oil and warming the ATF prior to moving off. I sort of wait until the temp gauge needle strikesthrough the middle of the 40.

 

[d w124]

Have a w211 320 CDI and does take an absolute age to warm up.

The other is a c124 and always warm this up as my thinking would be obvioulsy to warm the engine oil and warming the ATF prior to moving off. I sort of wait until the temp gauge needle strikesthrough the middle of the 40.

I always do that to,but don`t do it Germany
Few years back I did that in Germany,and the neighbour called the police

 

[The _Don]

Guys, whats the deal here...

Drive off straight away or warm the engine up??

I always warm my engine up at least for 5-10 mins

views and opinions please.

Drive off straight away

 

[BillyW124]

@ dash

 

[gkerr4]

i always leave it to warm up a little too - but this is a hotly contested subject!"

I like to have a little warmth in the cabin and also to allow the rear heater and mirror heaters to do their job - i usually start it and then start scraping the ice off the windows - i'm a bit obsessive so I like all windows to be completely clear before I drive off - I HATE HATE HATE seeing cars with drivers trying to drive through a little 2inch square 'peephole' in the screen.

i don't really care either way if it is good or bad for the engine. I'm sure the engine will have been through worse at either end of the it's testing spectrum .

 

[gkerr4]

I always do that to,but don`t do it Germany
Few years back I did that in Germany,and the neighbour called the police

I don't really undertstand - why would the neighbour call the police and what has it got to do with the police?

 

[d w124]

I don't really undertstand - why would the neighbour call the police and what has it got to do with the police?

You`ll find this really funny but They said I was making smoke outside their house out of a petrol car
You know ze Germans dude

 

[BillyW124]

perfektionists! i love it

 

[renault12ts]

i always leave it to warm up a little too - but this is a hotly contested subject!"

I like to have a little warmth in the cabin and also to allow the rear heater and mirror heaters to do their job - i usually start it and then start scraping the ice off the windows - i'm a bit obsessive so I like all windows to be completely clear before I drive off - I HATE HATE HATE seeing cars with drivers trying to drive through a little 2inch square 'peephole' in the screen.

i don't really care either way if it is good or bad for the engine. I'm sure the engine will have been through worse at either end of the it's testing spectrum .

I could leave my car running for half an hour on the driveway and still have no heat in the cabin.

 

[tagnut]

I don't really undertstand - why would the neighbour call the police and what has it got to do with the police?

IIRC, in Germany it is illegal to leave a vehicle engine idling for any prolonged period of time (don't know if there is a specific limit) while the vehicle is stationary

 

[gkerr4]

o right - I didn't realise - I worked in germany for a few months in 2000 - 2001 - they are a funny culture.

i remember working late in the evening in a mixed-nationality team and at exactly 6:30pm the german teams would be very apologietic but "have" to go - no problem I thought, it's been a long day.

at 7:30 - the "workers council" (union? is it?) rep would appear in the office to ensure there were no Germans still working - a civil offence apparently!!

 

[gkerr4]

I could leave my car running for half an hour on the driveway and still have no heat in the cabin.

mine starts to heat the cabin after a few minutes - even though the temp guage hasn't moved - I think we spoke about this on another thread didn't we? - we were wondering if there was something electric in there?!?! - it works anyway!

 

[kwakdonut]

Start car. Allow oil pressure to come up (approx 5-15 secs). Drive off!!

Also it helps if your car has heated seats, additional heater, lives in a garage.....

 

[BillyW124]

aaaahh i dont know about just driving off!!!

but if it is perfectly the norm to do this why do people like myself and others think warming is the way to go?!

need advtages and disadvantages of driving off or warming up

 

[kwakdonut]

Long, cold morning idles for a petrol engine will cause excessive wear due to fuel wash on the cylinder bores (due to choke/cold start), whether carb or injection engine.

Not same for diesel engines as the fuel is an oil rather than a hydrocarbon solvent but diesel engines will not warm as quick as the engine blocks, heads etc are much thicker due to the compression ratios need for diesel ignition (20/22:1 compared to maybe 8/9:1 for petrol). Also, as has been previously mentioned, diesel is much more efficient from cold (no cold start/choke required, glow-plugs do that) so therefore will generate less heat.

For example, at the moment, my E320 takes almost 3/4 of my journey to work (13 miles) to get up to 80c but a petrol (such as my other halfs Ford Fusion 1.4) takes possibly only a mile or so before being up to a reasonable temperature and kicking heat out from the vents.

If you drive off straight away, the engine and transmission will warm up quicker as obviously the engine will be revved. On petrols, the cold start will go off quicker, limiting fuel wash on the bores.

Also, at idle, many alternators are not running at max (regulated) voltage until above idle so you won't feel the full benefit from heated screens etc.

 

[BillyW124]

cheers Kwak,

how about this then...turn engine on, wait for high revs to drop to normal idle, then drive off?

All in all like you said MAX 15 seconds

My high idle on the c124 drop down say after 5 seconds. sometimes it doesnt even high idle at all.

 

[Shude]

Given the price of fuel these days I'd say it make decent sense to be away ASAP! The less time spent idling the better.

 

[racall]

What position

What position do you have the circulation knob on for max heat??,I find mine at 6pm is best. the others dont warm my feet.Auto and A/C off as well.