Idling from cold.....

Rev it gently, was my thought...

Well what prompted me to ask the question anyway was the thought...

" do I start it up... lock it up.... brew up... or do I "brew up... start up... sit on my bum with a slight throttle to warm it up?"

Cheers guys!

(bet my cuppa steams the window up!)

Tom

I start my diesel van up ten to twenty mins before leaving for work.

Fire it up, pull out the hand throttle about half way, and go in for a cuppa tea.

had the van almost ten years, its done nearly 180K. Done this every winter, doesn't seem to have done any harm.

sQuick..

Also sprach "Mogweed" :-

I fill a 2-litre conditioner bottle from the hot tap, add a couple of drips of dishwasher rinse aid and pour it slowly down the screen. This melts any frost and warms the screen enough to disperse any condensation on the inside. Jump in - start up and I'm on my merry way. Takes less than 30 seconds.

Also sprach "Will Reeve" :-

Add a couple of drops of dishwasher rinse aid. It raises the surface tension so that the water warms the screen but runs off leaving the screen dry. Not only is there nothing to refreeze, but also there's no evaporative cooling.

In reality any of the methods described will do. Cold mornings and cars have both been around long enough for designers and manufacturers to have taken them into account. Any manufacturer whose cars were likely to suffer ill effects from cold starting would quickly pay the commercial price. It suits oil manufacturers to try to scare the crap out of you but it's just alarmist bullshit.

Enjoy your cuppa and warm up your engine any way you like.

Steve

Will this work (rinse aid bit) in just normal washer water? (I use Halfords own-brand screenwash).

Pete.

Also sprach Pete Smith :-

I s'pose so - but I'd not want to try it. When you're squirting the windscreen you're trying to wet the screen to get the dirt off. Frost is different.

I haven't seen one even partially definitive answer yet - not surprising as it's a complicated issue and difficult to prove one way or another.

I've always believed in the conventional wisdom, but it's 30+ years old and I've never seen any proof. Has anyone considered that the conventional wisdom could be out of date? In the past 20 years we have had:

• electric fans - engine idling has less cooling than with mechanical fan, but when driving still has forced air cooling

• fuel injection/catalysts/electronic control - engine idles on much leaner mixture, less excess fuel to dilute the oil

• oil technology - lubrication has been vastly improved

• improvements in engine design - better manufacturing tolerances etc

I'm not saying this makes it better to idle an engine to warm it up, but I would like to hear arguments supported by evidence.

Biggles Remove packaging to e-mail me

Just fire it up, when it ticks over, go into your house, have a cup of tea/coffee/cigarette, go for a crap, come out of the house, car will be ready. Unless you are in a high crime area, never thought of that sorry. I leave mine on the driveway till I'm ready, not the car. I take longer to be ready every time !!!

"Biggles" wrote in message news:cr20e1$4v0$ snipped-for-privacy@news8.svr.pol.co.uk...

I don't know what the "conventional wisdom" is. I will not get into my car until the windows are ice free, the inside of the screen is condensation free, the mirrors are clear, etc., etc. A bonus of this is that the cabin temp will be nice and high too. Of course this only applies to those days where the temp is minus something, otherwise the car is ok. I once saw the most unbelievable thing caused by someone Not clearing their car properly. The scene is a very cold snap, no gritters on road, road like a skating rink. I start up car on driveway in cul de sac on my driveway early morning. Leave it to tick over, go for shower, shave, coffee etc. Look out the front windows to see if car looks defrosted, looks warm as toast. Stub out ciggie, put on jacket and go out to car. Reverse out drive with full visibility, go down to main road, Stop for bus going past. Bus tries to brake for Metro with a letter box scraped out of his front screen and side windows fully frosted coming out of street opposite. Bus has all wheels locked but skidding merrily and has horn on. Metro can't see a thing and is probably deaf, keeps coming out, gets collected by front of bus and whole lot go on their way down street. I follow once street is clear, overtake obstruction, assuming there are enough witnesses on the bus and proceed on journey to work. I did stop to see if the bus driver wanted a witness, but he said he thought he had enough to go on. I replied, so did I

Also sprach "Taz" :-

I used to live near several people who did that and I /hated/ them. They were up before I was and the fumes were dreadful. OK, this was before catalysts and when manual chokes were still around but it really was one of the most antisocial things to do. Eventually several of us, including a handful of shiftworkers went round and reasoned with 'em - which didn't work, so we got the police involved - which did. Apparently it's illegal to leave a car running but unattended.

Also sprach "Taz" :-

There's no excuse for that - but clearing the screen doesn't have to involve running a car for five minutes before driving off.

I think that's on a public road, surly I can do what I want on my drive? We are lucky and only leave for work at around 8am, the car is surprisingly quiet (Vauxhall V6 usually) the noisiest thing is the stupid air pump which apparently pumps air into the exhaust to help emissions! It's only on for about a minute. If we had a loud diesel I think I would think twice before leaving it clattering away but then again that's why I have a petrol!

Keep well all,

Will

P.S. About 5 years ago in the winter I was hit in the rear by someone who didn't bother to de-mist his screen before driving off. Ironically I did the same and decided to pull over at the curb just outside my house (completely legally) to de-mist before continuing my journey, about 5 minutes later I was hit (god knows how as the road was easily large enough for 4 cars abreast!) at 30mph by someone who by his own admission couldn't see out of the windscreen! Luckily I kept my seatbelt on and only had about a week of neck ache!

Ice scraper? De-icer? It's illegal to leave your engine running if the vehicle is unattended, even if you can lock it without turning the engine off. And if your car got stolen (smashed window or forced lock only takes seconds - you'd probably not even notice until it were too late) there's no way the insurance would pay up if you admit to leaving the engine running!

Darren

1. Cold engines run rich, the extra fuel doesn't get burnt and it washes the oil off the cylinders resulting in less lubrication.

1. Cold engine oil doesn't lubricate as well as warm/hot engine oil.

1. Engines and engine oil warm up very slowly when idling.

On a cold day it'll probably take around 10 miles to warm up fully, not

5 mins. In the summer probably around 5/6 miles. I'd probably go very gentle for about 4 miles, drive normally after that, and not thrash it until it's fully warm.

I drive away after 30s of idling.

OK, still no evidence to answer my or the OP's question one way or another. The safety issues etc are very interesting. I (and the OP if I'm not mistaken) are interested in knowing whether it is better for the engine to be warmed up on idle or by driving - i.e. which does less harm to the engine. It is obviously better to clear your windows before driving off, but as other posters have pointed out, there are various ways to do this, and that wasn't the question which was being asked.

So, can anyone provide evidence that it is better or worse *for the engine* (on a modern car) if it is warmed up on idle before driving off?

Biggles Remove packaging before e-mailing

Form the last time I played with test beds in 92, the bore wear was down to the acid from warming up , so the quicker you warmed it up the less bore wear you got, can't see any reason that would have changed.

That's on a test bed - but was any comparison made between the relative wear of idling with running under load while warming up? And what about the difference that forced air cooling (when driving along) makes to the warm up? - you don't get that when idling at rest.

Biggles Remove packaging before e-mailing