is it bad to leave the car idling?

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rh71

No Lifer
Aug 28, 2001
52,844
1,049
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In my Rodeo, whenever I start it up in the cold, it will usually go to about 1500RPM instantly. Like conjur, I let it drop to normal idle (about 1-2 mins) before I take off. In our Accord, there really isn't a way to tell by RPM, so I just let it go for a couple of mins, then pull out.

In either instance, I'll notice sluggishness for the first half mile down the road, then it'll be "warmed up" enough for highway action. Just don't gun it off the get-go.

I've also had instances where I leave it idling in the morning while I get ready myself (like a remote starter deal). After 15 minutes of that, the thing feels good to go as if I were already driving for miles.

So the more time you give it, the better, IMO. I've heard of people idling for an hour for whatever reason and it doesn't harm the car.
 

captains

Diamond Member
Mar 27, 2003
4,065
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i've gone over friends houses many times just to say whats up and end up watching a movie or something and come out of their house like 2- 3 hrs later with my car still running....just takes a toll on gas after a while
 

FuZoR

Diamond Member
Sep 22, 2001
4,422
1
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my car never warms up when its idle even if i wait like 5-10mins.. I drive less then 5mins and i lower the temp gauges cause its getting to hot heh

damn i hate winters
 

rh71

No Lifer
Aug 28, 2001
52,844
1,049
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Originally posted by: captains
i've gone over friends houses many times just to say whats up and end up watching a movie or something and come out of their house like 2- 3 hrs later with my car still running....just takes a toll on gas after a while
LOL... do you even bother to lock the doors ?

 

AsianriceX

Golden Member
Dec 30, 2001
1,318
1
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I usually wait till the idle RPM's drop to around 1000. I figure that the ECU knows more about how the engine is doing than I do, so it keeps the revs higher while it's cold in order to warm it up. These newfangled cars are smart.
 

captains

Diamond Member
Mar 27, 2003
4,065
1
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Originally posted by: rh71
Originally posted by: captains
i've gone over friends houses many times just to say whats up and end up watching a movie or something and come out of their house like 2- 3 hrs later with my car still running....just takes a toll on gas after a while
LOL... do you even bother to lock the doors ?

no....i'm in a decent neighbor hood....plus the way things are now, if some one took it they would be doin me a favor
 

Vic

Elite Member
Jun 12, 2001
50,422
14,337
136
No, it doesn't hurt a car at all to idle it for a while after a cold start. Better than putting it under load.
The reason that people are told not to warm up their cars anymore is that catalytic converters don't work when cold so, for the environment, people are encouraged to warm up their cars as quickly as possible (by driving them).

I usually warm up my car for about 1-2 mins every morning, but then again, it doesn't get very cold where I live and I keep my car garaged at night.

ALWAYS warm up your car for at least 10-15 seconds before driving. I'm always astonished to see people who just cold start their engine and then drive off immediately. If you have any respect for your car or the money you sink into it, at least let the oil circulate a little before driving off.
 

rh71

No Lifer
Aug 28, 2001
52,844
1,049
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Originally posted by: captains
Originally posted by: rh71
Originally posted by: captains
i've gone over friends houses many times just to say whats up and end up watching a movie or something and come out of their house like 2- 3 hrs later with my car still running....just takes a toll on gas after a while
LOL... do you even bother to lock the doors ?

no....i'm in a decent neighbor hood....plus the way things are now, if some one took it they would be doin me a favor
Heh I had an idea you were going to say it was a "worthless" car. I see people pull up to a store or walk-in ATM while leaving their car running. I know it's bad for the engine to start/stop all the time and I'd much rather leave it running also, but at least have a separate set of keys to lock the doors while you're in there. It's just not even worth the trouble of reporting a stolen car, let alone losing one. I wonder if you tell the cops that you left it unlocked... would they think you deserved it ? ;)

 

captains

Diamond Member
Mar 27, 2003
4,065
1
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Originally posted by: rh71
Originally posted by: captains
Originally posted by: rh71
Originally posted by: captains
i've gone over friends houses many times just to say whats up and end up watching a movie or something and come out of their house like 2- 3 hrs later with my car still running....just takes a toll on gas after a while
LOL... do you even bother to lock the doors ?

no....i'm in a decent neighbor hood....plus the way things are now, if some one took it they would be doin me a favor
Heh I had an idea you were going to say it was a "worthless" car. I see people pull up to a store or walk-in ATM while leaving their car running. I know it's bad for the engine to start/stop all the time and I'd much rather leave it running also, but at least have a separate set of keys to lock the doors while you're in there. It's just not even worth the trouble of reporting a stolen car, let alone losing one. I wonder if you tell the cops that you left it unlocked... would they think you deserved it ? ;)

its not that its a crappy car, its that with my driving record, in about a year i will be paying more in insurance then what the car is worth.....i have a remote starter in it so when i ever i stop at a 7-11 or something i just hit the button so my car stays running and i take my keys and lock the door. i dont really expect anyone to steal my car in the neighborhood i'm in, if it happens it happens though
 

Vic

Elite Member
Jun 12, 2001
50,422
14,337
136
Originally posted by: rh71
Originally posted by: captains
Originally posted by: rh71
Originally posted by: captains
i've gone over friends houses many times just to say whats up and end up watching a movie or something and come out of their house like 2- 3 hrs later with my car still running....just takes a toll on gas after a while
LOL... do you even bother to lock the doors ?
no....i'm in a decent neighbor hood....plus the way things are now, if some one took it they would be doin me a favor
Heh I had an idea you were going to say it was a "crappy" car. I see people pull up to a store or walk-in ATM while leaving their car running. I know it's bad for the engine to start/stop all the time and I'd much rather leave it running also, but at least have a separate set of keys to lock the doors while you're in there. It's just not even worth the trouble of reporting a stolen car, let alone losing one. I wonder if you tell the cops that you left it unlocked... would they think you deserved it ? ;)
There's also the fact that insurance companies won't pay for cars that are stolen while left running and unlocked with the keys inside. The insurance companies consider that to be negligence in protecting the insured property. Happened to a friend of mine. Luckily they found his a couple of weeks later (and not too badly stripped, just joyridded with the stereo ripped out). Otherwise, he would have been screwed.
 

Heisenberg

Lifer
Dec 21, 2001
10,621
1
0
Originally posted by: Roger
Vehicles with carbs, yes it hurts it.

Vehicles with fuel injection, no.
Why is it bad for carb'd vehicles?

/knows next-to-nothing about carburetors
 

Vic

Elite Member
Jun 12, 2001
50,422
14,337
136
Originally posted by: Roger
Vehicles with carbs, yes it hurts it.
How so? Just curious because every car with carbs that I ever owned was a cold-blooded bitch that would barely go down the road until it was warmed up.
 

Why is it bad for carb'd vehicles?

/knows next-to-nothing about carburetors

When cold, an engine needs a very rich mixture to run, on carbs this is accomplished throught the use of a choke (blocks off the airflow causing more fuel to be sucked into the intake), this greatly contributes to rapid piston and cylinder wear because of oil wash off along with the fact you are diluting the oil with unburnt gasoline.

This does not occur on fuel injected vehicles because of the precision fuel metering that fuel injection provides.


How so? Just curious because every car with carbs that I ever owned was a cold-blooded bitch that would barely go down the road until it was warmed up.

As stated, a choke is no where as accurate at delivering the richer mixture, your "cold bloddedness" as you stated is caused from too lean of a mixture and from the fact that gasoline will puddle on the cold intake manifold walls where as most fuel injection today has injectors directed at the back of the intake valve.

 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: Roger
Why is it bad for carb'd vehicles?

/knows next-to-nothing about carburetors

When cold, an engine needs a very rich mixture to run, on carbs this is accomplished throught the use of a choke (blocks off the airflow causing more fuel to be sucked into the intake), this greatly contributes to rapid piston and cylinder wear because of oil wash off along with the fact you are diluting the oil with unburnt gasoline.

This does not occur on fuel injected vehicles because of the precision fuel metering that fuel injection provides.


How so? Just curious because every car with carbs that I ever owned was a cold-blooded bitch that would barely go down the road until it was warmed up.

As stated, a choke is no where as accurate at delivering the richer mixture, your "cold bloddedness" as you stated is caused from too lean of a mixture and from the fact that gasoline will puddle on the cold intake manifold walls where as most fuel injection today has injectors directed at the back of the intake valve.

So the motor continues to run choked/rich?
 

Heisenberg

Lifer
Dec 21, 2001
10,621
1
0
Originally posted by: Roger
Why is it bad for carb'd vehicles?

/knows next-to-nothing about carburetors

When cold, an engine needs a very rich mixture to run, on carbs this is accomplished throught the use of a choke (blocks off the airflow causing more fuel to be sucked into the intake), this greatly contributes to rapid piston and cylinder wear because of oil wash off along with the fact you are diluting the oil with unburnt gasoline.

This does not occur on fuel injected vehicles because of the precision fuel metering that fuel injection provides.


How so? Just curious because every car with carbs that I ever owned was a cold-blooded bitch that would barely go down the road until it was warmed up.

As stated, a choke is no where as accurate at delivering the richer mixture, your "cold bloddedness" as you stated is caused from too lean of a mixture and from the fact that gasoline will puddle on the cold intake manifold walls where as most fuel injection today has injectors directed at the back of the intake valve.
Ah, I see now. :)
 

Ornery

Lifer
Oct 9, 1999
20,022
17
81
Hah! You guys are pikers when it comes to warming up a car! I start my wife's car at 6:20AM to take my oldest son up to the bus stop at 6:40AM. I back it in the drive, with the driver's door right at the end of the sidewalk, for my wife's easy exit at 7:40AM. I'll warm it up for her at 7:30AM when I fetch the paper at the end of the drive. I may walk out the door with her and start my car at 7:40AM, to warm it up to take my youngest son to school at 7:55AM.

I don't give a damn how hard it is on the car, if it is at all. This is one of the main functions of these cars, so they're going to pamper us, not the other way around! Mine still gets 17MPG and that's pure city driving with all that warm up time everyday.
 

stev0

Diamond Member
Dec 9, 2001
5,132
0
0
Originally posted by: CraigRT
I let my car idle for 15 mins every morning to get it warm inside.. (then again I am in Canada where it's like -20C) and without it idling for at least 15 mins it would still be below 0 in the car!!

ditto, i've got underground parking at my appartment so there my truck only warms up like 30sec - 1min. but when i've got 5min left of my last class of the day i will fire up my truck :)heart: astrostart). by the time i get to it (4-5 blocks away) it's been running for about 15 min and it's nice and warm inside, and the snow on the windsheild is uasually melted off :)

 

Asharus

Senior member
Oct 6, 2001
987
0
0
Why don't you guys just RTFM. Both my last and current car stated in the manual to start the car and immediately start driving, keeping the RPMs below 3k until out of the "blue zone".

I too, doubted the logic in this, until I presented the issue to the bimmer message boards. They informed me that the oil pressure is very low at idle and the oil will not properly circulate throughout the engine.
 

QueHuong

Platinum Member
Nov 21, 2001
2,098
0
0
I RTFM, it says not to let the car idle for more than 2 minutes - who else knows more about my car than the people who built in?
 

AgaBoogaBoo

Lifer
Feb 16, 2003
26,108
5
81
I haven't read all the posts yet, but letting it idle to heat up IMO is good. Why? Would you ever want to turn your car off and on 20 times in one minute? No, heating up and cooling down so fast is bad. Would you want your car to heat up very fast? I don't think so, IMO it should be gradual. I'd let it idle for a few minutes, and honestly, a few minutes of idling shouldn't hurt the engine. Again, these aren't based on facts but just my common sense so I"m probably wrong.
 

Pepsi90919

Lifer
Oct 9, 1999
25,162
1
81
In either instance, I'll notice sluggishness for the first half mile down the road, then it'll be "warmed up" enough for highway action.
because the computer retards the timing until it's warm enough. which means you just wasted your time 'warming up' your car. :)
 

PowerMacG5

Diamond Member
Apr 14, 2002
7,701
0
0
Originally posted by: Scarpozzi
Cops always leave their cars running....even when they're just eating donuts or reading the paper. I guess aside from gas consumption, it doesn't hurt. I installed a remote car starter in my jeep recently for the very reason of warming it up(or cooling it down in the summer)so I won't have to brave the elements. It was a fun project.
The thing is though cops have special engine and transmission coolers to allow for engine idle all day long.