Idling
- Thread starter Samf333
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No. It causes fuel dilution. Don't idle. Let it run maybe 30 seconds then gently drive away.
Id let it run not more than a few mins if it is extremely cold, but as GG said, you are best to drive gently to warm up a car.
If you can, I would say a block heater on a timer for an hour or two before leaving will help the car get warmer more quicky.
Originally Posted By: GutsyGecko
No. It causes fuel dilution.
Even with electronic multi-port fuel injection ?
No. It causes fuel dilution.
Even with electronic multi-port fuel injection ?
The fuel dilution issue is overblown. I make sure I warm my Mustang for 30min to an hour before I drive off. Then at the drive in I let it idle for up to 4 hours to run the heater.
If you want the oil warmer right away, then get a oil pan heater. They are inexpensive and don't use a lot of electricity. Then just start, and after a few seconds to let everything settle down, then drive away gently as was stated. If you want the best solution, a block heater combined with a oil pan heater, and your engine will love you on those very cold mornings.
Any kind of extended idling is not a good thing. It is less a problem if the engine rpm's are raised up a few hundred rpm when doing extended idling. Fuel dilution could be a problem, but proper lubrication could be the other. I have seen engines with spun rod and cam bearings because they idled excessively. But any kind of extended idling should be avoided if possible. Even commercial heavy diesels do not need the idling to warm up like they did in years gone by. And in some jurisdictions, they are limited to 15 min max.
Any kind of extended idling is not a good thing. It is less a problem if the engine rpm's are raised up a few hundred rpm when doing extended idling. Fuel dilution could be a problem, but proper lubrication could be the other. I have seen engines with spun rod and cam bearings because they idled excessively. But any kind of extended idling should be avoided if possible. Even commercial heavy diesels do not need the idling to warm up like they did in years gone by. And in some jurisdictions, they are limited to 15 min max.
Originally Posted By: Samf333
is extended idling bad after it is warmed up?
I would think that as long as the engine doesn't overheat and it's metering fuel like it's supposed to, it shouldn't be an issue.
is extended idling bad after it is warmed up?
I would think that as long as the engine doesn't overheat and it's metering fuel like it's supposed to, it shouldn't be an issue.
me too
Originally Posted By: Merkava_4
Originally Posted By: Samf333
is extended idling bad after it is warmed up?
I would think that as long as the engine doesn't overheat and it's metering fuel like it's supposed to, it shouldn't be an issue.
Originally Posted By: Merkava_4
Originally Posted By: Samf333
is extended idling bad after it is warmed up?
I would think that as long as the engine doesn't overheat and it's metering fuel like it's supposed to, it shouldn't be an issue.
Long idling to warm up an engine is not the best way from a wear stand point but, idle after a full warm-up is not that bad if like Merkava said.
IME extended operations at idle have almost no effect on a modern engine if all is well. But where we live low temps aren't much of an issue either.
Probably 90% of our work is done at exactly 1550 rpm, with small amounts at 1750 if we need it.
I do know that in the 'old daze' we were taught not to even turn the engines off if we weren't shutting down for at least 15 minutes or more. Just left them idling, a lot!
Probably 90% of our work is done at exactly 1550 rpm, with small amounts at 1750 if we need it.
I do know that in the 'old daze' we were taught not to even turn the engines off if we weren't shutting down for at least 15 minutes or more. Just left them idling, a lot!
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I just idle a cold-started engine until the temp needle begins to move,then drive as usual.
Pulled straight from a letter discussion on Car Talk between Click and Clack:
With the cold New England winter weather about to swoop down on us, I
have a queasy feeling in the pit of my stomach. Why, you ask? Because
every winter when my boyfriend and I get into my car, I start it, then
I put the car in gear after about 30 seconds and drive off. This
drives my boyfriend nuts, and I have to hear about "how bad it is for
my car" to put it into Drive before it warms up. He will start his car
and sit there for a good five to 10 minutes before he shifts into
Drive. My question is this: Am I really doing harm to my car by not
letting the engine run for 10 minutes? If not, how can I prove this to
him? I found an article in The New York Times a couple of years ago
that stated that nothing is gained by sitting in a freezing-cold car
while the motor is running before you shift into Drive. He thinks that
the reporter at the Times didn't know what he was talking about. But
he just might listen to you if you say it's OK. Please help! It's cold
here in Boston! -- Lisa
RAY: How do you prove it to him, Lisa? Hand him this column and ask
him to read the following aloud:
TOM: Dear Lisa's Boyfriend: You have your head so far up your tailpipe
on this one, it may be coming out your air intake.
RAY: How's that, Lisa? Will that do it? You're absolutely right, as is
the reporter from The New York Times. On modern, fuel-injected cars --
basically anything made in the past 20 years -- you're not helping the
car at all by warming it up for five or 10 minutes.
TOM: On older, carbureted cars, that kind of extended warm-up can
actually cause damage to the engine by diluting the oil with excess
fuel. So it's even worse if you have a really old heap.
RAY: But with modern cars, all you're doing with a long warm-up is
wasting gas, increasing pollution, raising the temperature of the
planet and making yourself 10 minutes late for your chiropractic
appointment. The proper procedure is to start the car. If it starts
and keeps running, put it in Drive and go. Go gently (don't back out
of your driveway and floor it right onto a highway entrance ramp),
because you'll be warming it up during your first few minutes of
driving, but DO drive it.
TOM: If it's bitterly cold out, like 10 or 20 degrees Fahrenheit or
lower, you can let it warm up for a minute or two to allow the oil to
thin out a bit and circulate completely. But other than that, if it
runs, driving it gently is the best way to warm it up.
RAY: So tell your boyfriend he not only needs to get off your case
about this, but he needs to stop warming up the car himself.
TOM: AND, to make up for all the misplaced grief he's given you over
the years, he needs to start going to bed 10 minutes before you do, to
warm up the bed for you on cold winter nights. That's a warm-up
activity he can do that's actually useful!
With the cold New England winter weather about to swoop down on us, I
have a queasy feeling in the pit of my stomach. Why, you ask? Because
every winter when my boyfriend and I get into my car, I start it, then
I put the car in gear after about 30 seconds and drive off. This
drives my boyfriend nuts, and I have to hear about "how bad it is for
my car" to put it into Drive before it warms up. He will start his car
and sit there for a good five to 10 minutes before he shifts into
Drive. My question is this: Am I really doing harm to my car by not
letting the engine run for 10 minutes? If not, how can I prove this to
him? I found an article in The New York Times a couple of years ago
that stated that nothing is gained by sitting in a freezing-cold car
while the motor is running before you shift into Drive. He thinks that
the reporter at the Times didn't know what he was talking about. But
he just might listen to you if you say it's OK. Please help! It's cold
here in Boston! -- Lisa
RAY: How do you prove it to him, Lisa? Hand him this column and ask
him to read the following aloud:
TOM: Dear Lisa's Boyfriend: You have your head so far up your tailpipe
on this one, it may be coming out your air intake.
RAY: How's that, Lisa? Will that do it? You're absolutely right, as is
the reporter from The New York Times. On modern, fuel-injected cars --
basically anything made in the past 20 years -- you're not helping the
car at all by warming it up for five or 10 minutes.
TOM: On older, carbureted cars, that kind of extended warm-up can
actually cause damage to the engine by diluting the oil with excess
fuel. So it's even worse if you have a really old heap.
RAY: But with modern cars, all you're doing with a long warm-up is
wasting gas, increasing pollution, raising the temperature of the
planet and making yourself 10 minutes late for your chiropractic
appointment. The proper procedure is to start the car. If it starts
and keeps running, put it in Drive and go. Go gently (don't back out
of your driveway and floor it right onto a highway entrance ramp),
because you'll be warming it up during your first few minutes of
driving, but DO drive it.
TOM: If it's bitterly cold out, like 10 or 20 degrees Fahrenheit or
lower, you can let it warm up for a minute or two to allow the oil to
thin out a bit and circulate completely. But other than that, if it
runs, driving it gently is the best way to warm it up.
RAY: So tell your boyfriend he not only needs to get off your case
about this, but he needs to stop warming up the car himself.
TOM: AND, to make up for all the misplaced grief he's given you over
the years, he needs to start going to bed 10 minutes before you do, to
warm up the bed for you on cold winter nights. That's a warm-up
activity he can do that's actually useful!
Last edited:
I doubt it warms the oil that much. The combustion chambers will be up to temp in a pretty short time so there is no need for an extended warm up.
Old engines had a choke and the cold would cause the fuel to condense in the cylinders. Modern FI engines don't have this kind of problem.
If you read about the modern oils here on BITOG, you will find that modern, low viscosity synthetic oils provide good flow even at low temps.
Old engines had a choke and the cold would cause the fuel to condense in the cylinders. Modern FI engines don't have this kind of problem.
If you read about the modern oils here on BITOG, you will find that modern, low viscosity synthetic oils provide good flow even at low temps.
With todays fuel injection its not an issue. BUT if you have an older car with carbs, I would not let it idle longer then a few minutes... If its in storage, I would let it sit not started until you can drive it for 30 minutes.
Originally Posted By: turtlevette
The fuel dilution issue is overblown. I make sure I warm my Mustang for 30min to an hour before I drive off. Then at the drive in I let it idle for up to 4 hours to run the heater.
Enjoy that rich carbon monoxide as it filters into your blood!
Where do you find a drive-in these days?
The fuel dilution issue is overblown. I make sure I warm my Mustang for 30min to an hour before I drive off. Then at the drive in I let it idle for up to 4 hours to run the heater.
Enjoy that rich carbon monoxide as it filters into your blood!
Where do you find a drive-in these days?
My procedure, that I have followed for 40 years, is to let the car warm up 1 minute if it's cold and 30 secs if it's not. Very cold means two minutes. You decide what's cold. Drive gently until warm. This applies to overnight starts. An engine that's already warm? Just get in and go no matter how cold it is outside.
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