Warming up a car in the morning

CyberGhost

I always warm my car up in the morning(VW Polo). Couple of minutes on a standstill.

Why I'm asking is cause, I just read in BMW 5 series' manual a little paragraph which said that standstill warm ups aren't needed for either a diesel or a petrol, you just have drive at moderate speed for couple of minutes.

What are your opinions on that? is that only for the new generation engines?

It struck me odd cause as I knew you should always warm up your car on a standstill before driving off, so the oil gets into all the parts of an engine.

Tails142

once you dont reach excessive rev speeds, for example, +3000rpm wear while the engine is cold will be minimal.

so as long as you dont put the foot down there is no real need to wait for the oil temp to rise.

CyberGhost

Thanks Tails, I didn't know about that.

mike65

Modern multigrade oil engines should'nt be left to warm on idle from cold, its tempting of course on a freezing morning esp if fogged/iced, but that what demisters/icescrappers/carboard is for. As said when moving on cold don't over-rev.

Mike.

niceirishfella

hi,

i own a 530d and it warms up very quickly..........and as the engine has a high grade fully synth oil........there are no real worries.

carefull leaving the keys in the vw on the warm up.......if it got stolen - your insurance is void.:eek:

miss enzo

my FTO warms up fast enuf but i never drive above 3k revs until its warm.

CyberGhost

niceirishfella wrote: »

carefull leaving the keys in the vw on the warm up.......if it got stolen - your insurance is void.:eek:

Thanks for the tip but, it's a 1.0L 99' Polo, I don't think any self respecting thief/boy racer thief would take it

They tried to steal my 93' 1100 euro civic though

colm_mcm

miss enzo wrote: »

my FTO warms up fast enuf but i never drive above 3k revs until its warm.

I remote start mine and let it run for 20 mins or so so I can treat the neighbours to my MIVEC alarm clock!

niceirishfella

CyberGhost wrote: »

Thanks for the tip but, it's a 1.0L 99' Polo, I don't think any self respecting thief/boy racer thief would take it

They tried to steal my 93' 1100 euro civic though

LOL...........did i mention that the Cops can prosecute you also if the car gets stolen thru' you leaving the keys in it running...........:(........Sad but true.

cpoh1

Remember lads the temp gauge on your dash reads the coolant temperature NOT the oil temp. Just because the coolant has reached optimum temp doesnt mean your oil has too, my oil usually takes a good 10 minutes more than my coolant to hit 80-90 degrees.

JohnCleary

There's much difference in opinion on the forum about this (I can remembe ranother thread last year)

Some people say it's good to have the engine warm before driving off, other's say it's bad to leave the engine idling there for ages

What I do with a 320d... Start the engine, get radio gps etc. ready (Usually about 1 min) and then I don't drive over 2k rpm for about 10 mins (God help ya if you're stuck behind me because I drive like a granny until my engine is warm). I don't pay much attention to the temp sensor as this only senses the coolant temprature. Your engine is ready for high RPM's when the OIL is warm (Which can take twice as long as the coolant)

Just my opinion....

colm_mcm

an oil temp gauge is a handy thing to have, most cars don't have them these days.

kona

its extremly bad to leave a engine running, without a load, to warm up.
This increases the chances of localised hotspots occuring, even if the coolant temperature is still reading in the blue.
Also true about your oil temperature

colm_mcm

how bad is it? will it actually cause any damage or have any effect on my car?

JohnCleary

colm_mcm wrote: »

how bad is it? will it actually cause any damage or have any effect on my car?

I was told by a mechanic that's it's really bad to leave an engine idling under no load for a long time. I think he said it 'polishes' the cylinders or something. I used to leave the boat engine idling for a while and yer man came running down the jetty after me telling me to run the engine under light load until warmed up

My oul man is responsible for the running of really big generators (run by diesel engines) and he said he never run's them without load. ie. He starts the engine and puts a load on straight away

colm_mcm

maybe I'm just lucky that any of my cars haven't ever given any engine trouble, despite every one of them being idled to death on cold mornings!

cantdecide

JohnCleary wrote: »

when the OIL is warm (Which can take twice as long as the coolant).

I have an oil guage and it takes at least twice as long...

kona

colm_mcm wrote: »

how bad is it? will it actually cause any damage or have any effect on my car?

extremly bad, in fact idling is bad for a engine, even when warmed up.

when idling fuel doesnt completely combust, so as pointed out above, this damages the pistons, valves, exhaust manifolds etc. this may not cause a breakdown in a short time frame, but it all adds up when the engine has high mileage, and oter things start to fail, also it will probably cause your car to lose performance and increase fuel consumption.

also, it costs a fortune, pollutes more than a car in motion.

as for hotspots, certain engine designs, the hot spots can occur around the cylinders furthest from the water pump
also, its bad as when the water reaches a set temperature, the thermostat opens and floods the block /head with colder water,
the resulting thermal shock has been known to warp heads/and crack blocks...a example is the rover K-series.

a engine is designed to be most efficient under a load and in a certain rev-range.
while the materials in a engine are at their optimum at a given temperature, for example steel is brittle at lower temperatures, so if you are in a crash on a cold day, you will be more likely to die that in a warmer climate...thats why car bumpers are now polymers and not steel.
so pushing a engine while cold can lead to bearings, cams, rockers, crankshafts, gears all having premature wear or even lead to them failing.

Esel

My received wisdom is never let the engine idle from cold. I always drive away immediately after starting, never exceeding 2000rpm until temp guage is at normal.

Didn't know about oil temp though. Would have thought that any good multigrade oil is giving sufficient lubrication once the engine pressurises the system?

niceirishfella

ahhhhhhhhhhhhhhhhhhhhh, so the general consensus so far is to NOT start the car to warm it up and let it Idle in the morning...........

Instead - have a nice big Fooking HOT BOWL OF PORRIDGE!

E92

The best thing to do is start and go, but drive gently till it's warmed up and start building it up progressively(which is what I do). Revving engines at idle is bad for them, they need to be put under load(why I don't know but it's what I've been told is the best thing to do).

smemon

revving FTW

the harder we rev, the warmer we get

the only time i'd start up then idle is if i'm stuck in a parking lot, frozen windows etc and no water on hand...

Type 17

Driving off when cold (but keeping revs sensible) warms the engine up faster than idling for the same time period anyway (Driving out of a suburban estate into stationary traffic doesn't count ).

However, if you're worried about driving with a cold (fogged-up/icy) windscreen, try boiling half a kettle-full of water (resist the urge to hit quick-reply now, keep reading :cool: ) and then, when it is boiled, top it up to the max with cold water from the tap to get a kettle full of WARM water*.
Pour the water all over the windscreen and any other windows. Pour a lot of it over the windscreen, until the kettle is empty.

"Big deal" says you, "sure I knew that it would melt any ice, so what's the point?"

Apart from ice-removal, the real payoff is that you have warmed the glass up to a point where it will not fog up when you get into the car and breathe out on its inside surface (scrapers, de-icer, or cardboard don't do this) - it's like getting into a car that has been left running for 20 minutes, but without actually ruining your engine and polluting the planet. I warm the glass up like this on cold mornings even when there is no ice on it.

*You should be able to put your hand in it comfortably - for the two people on earth who aren't already aware, very hot/boiling water WILL crack your cold windscreen, especially if it already has a fault/chip in it.

unkel

Bloody hell!

I suppose engines can take a lot more abuse these days than they used to, but still...

As some posters said, it is best to drive off (nearly) immediately and to use as much of the engine's power as possible while keeping the revs down. 100km/h on a national road in top gear would be just about perfect for most cars

Andrewf20

My routine is to get into the car, turn on the engine, put on my seat belt, and 20 seconds later get going at low revs to get the oil pump running at some sort of speed. When the temp gauge hits its operating temp, I wait a few more mins then open her up!

aoife2k

E92 wrote: »

Revving engines at idle is bad for them, they need to be put under load(why I don't know but it's what I've been told is the best thing to do).

And some of us who have to put our cars through the NCT sit back and listen to them rev the bejaysus out of our cars??? :O :O No wonder mine wouldn't take me home afterwards

drdre

niceirishfella wrote: »

LOL...........did i mention that the Cops can prosecute you also if the car gets stolen thru' you leaving the keys in it running...........:(........Sad but true.

Never heard that before

Henry Ford III

Start it and then drive it gently until engine is thoroughly warmed up.

antodeco

Unfortunatley I live less than 5 minutes away from the m50. So i generally let it idle for around 2 minutes then drive off along my merry way. Not much else I can do about it though! Ive been wanting to get an oil temp gauge fitted, but I have no idea where would do this for me!!

cjt156

antodeco wrote: »

Unfortunatley I live less than 5 minutes away from the m50.

Me too, I do as others have said, keep the revs down till its nicely warmed up. Do you have a rev-counter? 3k revs in top gear is about motorway speed.

MGrah

niceirishfella wrote: »

LOL...........did i mention that the Cops can prosecute you also if the car gets stolen thru' you leaving the keys in it running...........:(........Sad but true.

drdre wrote: »

Never heard that before

That's probably because the way it's written is a bit misleading. AFAIK it's illegal to leave a car "unattended" while the engine is running. Assuming that you would have to do this in order for it to be stolen I'd imagine that it is this that you could be prosecuted for, rather than aiding and abetting the car thief by providing them with the keys and starting the enigne for them.