Times Have Changed: Cold Starting

Has anyone in the north country noticed that on very cold, below zero F
mornings almost every vehicle starts right up. Twenty years ago and back, it
was very typical for many if not most cars to die during the starting
process. Possible reasons:

Near universal use of 5W-30 oils and more common use of synthetics. (10W-40
used to be the most common oil used).

More efficient starters.

Better battery/charging technology.

More common electronic ignitions and distributors.

Richard.

Richard wrote:

> Has anyone in the north country noticed that on very cold, below zero F
> mornings almost every vehicle starts right up. Twenty years ago and back, it
> was very typical for many if not most cars to die during the starting
> process. Possible reasons:
>
> Near universal use of 5W-30 oils and more common use of synthetics. (10W-40
> used to be the most common oil used).
Nope
>
> More efficient starters.
Nope
>
> Better battery/charging technology.
Nope
>
> More common electronic ignitions and distributors.
Nope


Its ALL because of multi-port high-pressure electronic fuel injection
that can keep the mixture spot-on where it needs to be for any engine
temperature, and doesn't depend on fully vaporizing the fuel upstream in
the intake manifold. A carburetor has a REALLY hard time keeping the
mixture anywhere near optimized in sub-zero temperatures, especially
through the starting process where the air flow varies from almost none
(cranking) to fairly high (fast idle) in a big hurry. In fact, a carb
works by pumping a small puddle of fuel into the manifold before
cranking (remember "depress accelerator fully twice and release"?) to
aid start up, since it can't possibly add enough fuel during cranking.
And once the engine fires, that slug of fuel immediately makes the
mixture too rich for a few seconds until it burns out... at which time
it *may* go too lean again for a few seconds and the engine may stall if
you're not quick enough at fluttering the accelerator pedal to pump more
fuel in.


Frankly, I kinda miss that spluttering, snorting, shaking process for
the first 30 seconds or so after start-up. Sounds really neat on a
big-block v8 :-)

On Thu, 20 Jan 2005, Steve wrote:

> > Near universal use of 5W-30 oils and more common use of synthetics.
> > (10W-40 used to be the most common oil used).

> Nope

Actually, Steve, yeah, that is one of the factors in the much greater ease
of super-cold starts. You live in Texas. I live in Toronto. That alone
makes me more qualified to comment on it than you (which is hardly a fair
exchange: You get to have barbecues and mow your lawn in the middle of
January, I get to prattle-on about cold starts. No fair.) What's more,
I've got direct and recent (last month) experience with the difference oil
weight makes in ability and ease of starting an engine from cold. So,
shutchyer mouth, you!

> Its ALL because of multi-port high-pressure electronic fuel injection

Naw, it isn't. That's a major factor, but certainly not the only one. EFI
makes newer vehicles much less tricky to start in the very cold, but other
factors apply to new and old cars alike. Oils with lower pour points and
better cold pumpability, gasolines that burn cleaner (leaving the spark
plugs cleaner so they require less arcover voltage), etc.

DS

Daniel J. Stern wrote:
> On Thu, 20 Jan 2005, Steve wrote:
>
>
>>>Near universal use of 5W-30 oils and more common use of synthetics.
>>>(10W-40 used to be the most common oil used).
>
>
>>Nope
>
>
> Actually, Steve, yeah, that is one of the factors in the much greater ease
> of super-cold starts. You live in Texas.

While I'm sure that the better oils increase cranking speed and allow
the engine to start quicker and idle with less effort, I don't think it
has anything to do with the sputter/die/restart that everyone used to
know about with carbureted cars.

I live in Toronto. That alone
> makes me more qualified to comment on it than you (which is hardly a fair
> exchange: You get to have barbecues and mow your lawn in the middle of
> January, I get to prattle-on about cold starts. No fair.) What's more,
> I've got direct and recent (last month) experience with the difference oil
> weight makes in ability and ease of starting an engine from cold. So,
> shutchyer mouth, you!
>

You can come mow my lawn in January ANYTIME, if you miss mowing lawns so
much :-p And maybe you can snort some cedar pollen while you're at it so
I don't have to breathe it:-)

>
>>Its ALL because of multi-port high-pressure electronic fuel injection
>
>
> Naw, it isn't. That's a major factor, but certainly not the only one. EFI
> makes newer vehicles much less tricky to start in the very cold, but other
> factors apply to new and old cars alike. Oils with lower pour points and
> better cold pumpability, gasolines that burn cleaner (leaving the spark
> plugs cleaner so they require less arcover voltage), etc.
>
> DS

Again, I don't really disagree, but I don't think any of that has so
much to do with start/sputter/die/restart as EFI does. EFI can meter,
vaporize, and evenly distribute fuel FAR better at low temperatures than
a carburetor can, while at higher temperatures the difference is far
less noticeable. Oil thickness, plug condition, and battery power all
matter, but those are second or third-order effects compared to the
better fuel control from MPEFI. And there's even a noticeable difference
beetween low-pressure throttle-body injected cars and moder
high-pressure EFI cars in the "cold" weather we get here in Texas, too.
TBI cars often gripe and grumble a lot like carbureted cars because the
intake manifolds are "wet" and fuel distribution is very poor in cold
temps, whereas MPI cars almost never do.

On Thu, 20 Jan 2005, Steve wrote:

> While I'm sure that the better oils increase cranking speed and allow
> the engine to start quicker and idle with less effort, I don't think it
> has anything to do with the sputter/die/restart that everyone used to
> know about with carbureted cars.

And I'm telling you, from firsthand experience, that you're wrong on this
exact point. With 15w50 Mobil-1 at 20 below (C), it took two or three
starts for the engine to stay running. With 5w30 Mobil-1 at 20 below (C)
and no other changes, the engine stays running after the first start.

Cranking speed is pretty irrelevant unless an engine is so whipped that
the compression pressure leaks past the rings so fast that a high cranking
speed is needed. GM proved in the early 1960s that a typical passenger car
engine (of the day!) would start at cranking speeds as low as 6rpm.

> You can come mow my lawn in January ANYTIME, if you miss mowing lawns so
> much :-p And maybe you can snort some cedar pollen while you're at it so
> I don't have to breathe it:-)

Fine. I'll accept payment in trips to Kreuz'.

"Steve" > wrote in message
...
> Richard wrote:
>
>> Has anyone in the north country noticed that on very cold, below zero F
>> mornings almost every vehicle starts right up. Twenty years ago and back,
>> it was very typical for many if not most cars to die during the starting
>> process. Possible reasons:
>>
>> Near universal use of 5W-30 oils and more common use of synthetics.
>> (10W-40 used to be the most common oil used).
> Nope
>>
>> More efficient starters.
> Nope
>>
>> Better battery/charging technology.
> Nope
>>
>> More common electronic ignitions and distributors.
> Nope
>
>
> Its ALL because of multi-port high-pressure electronic fuel injection that
> can keep the mixture spot-on where it needs to be for any engine
> temperature, and doesn't depend on fully vaporizing the fuel upstream in
> the intake manifold. A carburetor has a REALLY hard time keeping the
> mixture anywhere near optimized in sub-zero temperatures, especially
> through the starting process where the air flow varies from almost none
> (cranking) to fairly high (fast idle) in a big hurry. In fact, a carb
> works by pumping a small puddle of fuel into the manifold before cranking
> (remember "depress accelerator fully twice and release"?) to aid start up,
> since it can't possibly add enough fuel during cranking. And once the
> engine fires, that slug of fuel immediately makes the mixture too rich for
> a few seconds until it burns out... at which time it *may* go too lean
> again for a few seconds and the engine may stall if you're not quick
> enough at fluttering the accelerator pedal to pump more fuel in.
>
>

Steve,

I hate to agree with Dan but "always", "all", "none", and "never" are almost
always the wrong answer. :>

Art

Richard wrote:
> Has anyone in the north country noticed that on very cold, below zero
F
> mornings almost every vehicle starts right up. Twenty years ago and
back, it
> was very typical for many if not most cars to die during the starting

> process. Possible reasons:
>
> Near universal use of 5W-30 oils and more common use of synthetics.
(10W-40
> used to be the most common oil used).
>
> More efficient starters.
>
> Better battery/charging technology.
>
> More common electronic ignitions and distributors.
>
> Richard.

The problem that I usually had on older cars was the choke. A light tap
on the accelerator was needed to set it. Too much would flood it. Then
there was the problem of the choke not disengaging when it should,
causing a rich air/fuel mix. EFI and AIS stepper motors pretty much
eliminated these problems.

One of the most troublesome setups that I had, was a Dodge Caravan with
the 2.6 and the Minuki carb. The choke never worked right from day one.
-Kirk Matheson

Richard wrote:

> Has anyone in the north country noticed that on very cold, below zero F
> mornings almost every vehicle starts right up. Twenty years ago and back, it
> was very typical for many if not most cars to die during the starting
> process. Possible reasons:
>
> Near universal use of 5W-30 oils and more common use of synthetics. (10W-40
> used to be the most common oil used).
>
> More efficient starters.
>
> Better battery/charging technology.
>
> More common electronic ignitions and distributors.
>
> Richard.
>
>

I think computer controlled fuel injection vs. carburetion is the main
reason, but I don't disagree with anything you list above.


Matt

In article ch.edu>,
"Daniel J. Stern" > wrote:

> Cranking speed is pretty irrelevant unless an engine is so whipped that
> the compression pressure leaks past the rings so fast that a high cranking
> speed is needed. GM proved in the early 1960s that a typical passenger car
> engine (of the day!) would start at cranking speeds as low as 6rpm.

Hell, my old, but reasonably healthy, '82 Mazda 626 will push-start in
third gear with somewhere between three and five feet of roll - not a
"fast" roll, either, although it does fire even quicker if I can get up
some serious speed before popping the clutch - just "moving" - *MAYBE* 1
or 2 MPH, if that. In reverse, a foot or so of roll, at *WAY* below
typical walking speed, and a quick clutch-bump is all it takes to fire
it up every time. Dunno what the effective RPM is in either case (too
lazy to do the math) but whatever the number, it's obviously sufficient
for this beast

Guess that means it ain't quite whipped yet...

This saved my bacon one night at about 3 in the AM... Stopped out in the
middle of nowhere to watch the Perseid meteor shower dropping something
like 80 streaks per minute before continuing on my newspaper route, and
when I decided it was time to go, the starter said "Nah, I wanna stay
here and watch the sky-show" (Turned out later to be the starter
literally falling apart - One of the two long screws that held the
end-caps on it had vibrated loose, allowing some flex, which bound the
bearings - minor miracle: The screw that fell out dropped into a groove
in the engine cradle, where it rode safely until I found it later that
day while I was doing the wrenching to change out the starter.)

Damn fool me had decided to stop at the bottom of a little valley, or
maybe gulley would be the better word, in order to screen out the lights
on the horizon that were interfering with viewing the meteors - Great
view, but both directions were uphill - Figured I was screwed royally.
Grunted and heaved and cussed and sweated, and probably strained
something, but finally managed to get the front wheels about 2-3 feet up
the forward incline before gravity took over and started pushing me back
down the slope. Reached in and set the P-brake, sat down and caught my
breath, then turned it on, put it in reverse, mashed the clutch, and
released the brake. It started rolling back, exactly as expected. It
might have managed to hit the dizzying speed of half a mile an hour by
the time I bumped the clutch. The front end was still on the slope when
the engine fired up.

--
Don Bruder - - New Email policy in effect as of Feb. 21, 2004.
Short form: I'm trashing EVERY E-mail that doesn't contain a password in the
subject unless it comes from a "whitelisted" (pre-approved by me) address.
See <http://www.sonic.net/~dakidd/main/contact.html> for full details.

On Fri, 21 Jan 2005, Don Bruder wrote:

> > Cranking speed is pretty irrelevant unless an engine is so whipped
> > that the compression pressure leaks past the rings so fast that a high
> > cranking speed is needed. GM proved in the early 1960s that a typical
> > passenger car engine (of the day!) would start at cranking speeds as
> > low as 6rpm.

> Hell, my old, but reasonably healthy, '82 Mazda 626 will push-start in
> third gear with somewhere between three and five feet of roll

My '91 Spirit R/T would reliably start by just turning the ignition "on",
putting the trans in "Reverse", releasing the parking brake, rolling a few
feet down the driveway, then releasing the clutch. Two compressions was
all it took.