1990 accord - winter gas mileage

Is it a better idea to idle the car for 5min before driving it?

-vlad

On Tue, 30 Jan 2007 22:22:53 -0600, Gordon McGrew wrote:

> On 30 Jan 2007 08:08:17 -0800, wrote:
>
>>On Jan 30, 9:08 am, Vlad Ciubotariu > wrote:
>>> Thank you all,
>>>
>>> Yes, all my trips are 1-2 km to the grocery store and back at around -15C
>>> in Canada. I never had these problems a few months ago when it was still
>>> above 0.
>>>
>>> Vlad
>>Sure..The choke/fast idle/ECU rich mix is going on longer until it
>>warms up.
>>Once warm, there shouldn't be a whole lot of difference. But when
>>cold,
>>they drink the gas. And if it takes a good while longer to warm up,
>>just
>>that much more gas.. If you do many short trips in the cold wx, it's
>>going
>>to drink more gas. The car barely gets a chance to fully warm, and
>>every
>>time you go again, the car is probably cold again, and has to start
>>over.
>>MK
>
> This use is also very hard on the engine. There is going to be a ton
> of condensation and unburned gas in the crankcase and exhaust. If you
> are using the car this way, you should take it on a 20+ km drive once
> a week and change the oil every 3 months.

Vlad Ciubotariu > wrote in
news
> Is it a better idea to idle the car for 5min before driving it?



No. That's a BAD idea. You see people doing that, go up and give them a
smack upside the head. It's not good for the car to do that regularly.

It's a better idea to take the car for an hour's highway drive once a week.
This will get the oil hot enough to burn off all the water and gas that's
been collecting in it during your one-mile toodles to the grocery store.

An weekly hour's drive will also exercise the brakes, suspension and the
various seals, helping to prolong their lives and stave off trouble.



--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

On Thu, 01 Feb 2007 02:09:57 +0000, Tegger wrote:

> Vlad Ciubotariu > wrote in
> news >
>> Is it a better idea to idle the car for 5min before driving it?
>
>
>
> No. That's a BAD idea. You see people doing that, go up and give them a
> smack upside the head. It's not good for the car to do that regularly.
>
> It's a better idea to take the car for an hour's highway drive once a week.
> This will get the oil hot enough to burn off all the water and gas that's
> been collecting in it during your one-mile toodles to the grocery store.
>
> An weekly hour's drive will also exercise the brakes, suspension and the
> various seals, helping to prolong their lives and stave off trouble.
>
>
>

This has been asked before, but I have never seen a logical answer
provided (since I've been here, anyhow)...

WHY is it a bad idea? I understand that Honda recommends against it, but
what is the rationale? What is the negative effect on the engine from
idling for 5-10 minutes to get the heat going when it is 5 degrees outside?

I have taken to the habit of starting the car, brushing off the snow and
ice, and getting on the road, simply because Honda says so. I'd love to
know exactly why they say so...

Joe LaVigne wrote:
> On Thu, 01 Feb 2007 02:09:57 +0000, Tegger wrote:
>
>> Vlad Ciubotariu > wrote in
>> news >>
>>> Is it a better idea to idle the car for 5min before driving it?
>>
>>
>> No. That's a BAD idea. You see people doing that, go up and give them a
>> smack upside the head. It's not good for the car to do that regularly.
>>
>> It's a better idea to take the car for an hour's highway drive once a week.
>> This will get the oil hot enough to burn off all the water and gas that's
>> been collecting in it during your one-mile toodles to the grocery store.
>>
>> An weekly hour's drive will also exercise the brakes, suspension and the
>> various seals, helping to prolong their lives and stave off trouble.
>>
>>
>>
>
> This has been asked before, but I have never seen a logical answer
> provided (since I've been here, anyhow)...
>
> WHY is it a bad idea? I understand that Honda recommends against it, but
> what is the rationale? What is the negative effect on the engine from
> idling for 5-10 minutes to get the heat going when it is 5 degrees outside?
>
> I have taken to the habit of starting the car, brushing off the snow and
> ice, and getting on the road, simply because Honda says so. I'd love to
> know exactly why they say so...

here's what i've been told: 95% of all ring/cylinder wear occurs during
warmup. the longer warmup takes, the longer you're in the high wear
phase. an engine idling takes ages, an engine driven gets there quickly.

i understand that it's partly a lubricant viscosity thing and partly a
lubricant dilution thing because unburnt gasoline can condense on cold
cylinder walls and dilute the oil film. diesels, which have the same
factors involved, experience much less ring/cylinder wear because diesel
condensate is a lubricant, gas condensate is not.

jim beam > wrote in
:

> Joe LaVigne wrote:
>> On Thu, 01 Feb 2007 02:09:57 +0000, Tegger wrote:
>>
>>> Vlad Ciubotariu > wrote in
>>> news >>>
>>>> Is it a better idea to idle the car for 5min before driving it?
>>>
>>>
>>> No. That's a BAD idea. You see people doing that, go up and give
>>> them a smack upside the head. It's not good for the car to do that
>>> regularly.
>>>
>>> It's a better idea to take the car for an hour's highway drive once
>>> a week. This will get the oil hot enough to burn off all the water
>>> and gas that's been collecting in it during your one-mile toodles to
>>> the grocery store.
>>>
>>> An weekly hour's drive will also exercise the brakes, suspension and
>>> the various seals, helping to prolong their lives and stave off
>>> trouble.
>>>
>>>
>>>
>>
>> This has been asked before, but I have never seen a logical answer
>> provided (since I've been here, anyhow)...
>>
>> WHY is it a bad idea? I understand that Honda recommends against it,
>> but what is the rationale? What is the negative effect on the engine
>> from idling for 5-10 minutes to get the heat going when it is 5
>> degrees outside?
>>
>> I have taken to the habit of starting the car, brushing off the snow
>> and ice, and getting on the road, simply because Honda says so. I'd
>> love to know exactly why they say so...
>
> here's what i've been told: 95% of all ring/cylinder wear occurs
> during warmup. the longer warmup takes, the longer you're in the high
> wear phase. an engine idling takes ages, an engine driven gets there
> quickly.
>
>
> i understand that it's partly a lubricant viscosity thing and partly a
> lubricant dilution thing because unburnt gasoline can condense on cold
> cylinder walls and dilute the oil film. diesels, which have the same
> factors involved, experience much less ring/cylinder wear because
> diesel condensate is a lubricant, gas condensate is not.
>



Correct.

Extended cold idling periods dump tons of gas and water into the oil,
since the engine warms up so much more slowly. It takes longer full-hot
driving to boil all that off. This also contributes to sludge and
varnish buildup.

On the other hand, idling the car when it's already fully warm does not
cause the same problem, so that's OK.

The only benefit to extended cold idling is visibility: the windows will
be more completely cleared (if frosted up, that is), so you can more
safely see where you're going.

--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

On Thu, 01 Feb 2007 14:17:03 +0000, Tegger wrote:

>
> The only benefit to extended cold idling is visibility: the windows will
> be more completely cleared (if frosted up, that is), so you can more
> safely see where you're going.
>

Thanks, Jim and Tegger, for excellent information...

I will continue to do as I have been... Basically warm it as long as it
takes to brush it off and defog the windows, then get rolling...