Who waits for the RPMs to settle before ...?

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I'm unsure what prompted me to do this, but do any of y'all wait for the RPMs to settle after a cold start before shifting into gear?

What's the precise reason for the higher revs to begin with? And is it at all beneficial to allow the engine to settle down like I have a tendency of doing?
 
start car let run for 15-20s, back out of garage, sit there 15-30s while I wait on traffic, adjust radio etc.. drive away with light throttle.
 
Originally Posted by 2010Civic
With a manual transmission I don't mind as much taking off with the revs up.


The only manual vehicle in my stable, a '99 Wrangler with the 4.0, it settles down to normal idle speed basically immediately.
 
I wait. I think it was beneficial years ago but not as much now. My vehicles seem to run better if I wait but that may just be me.
 
Originally Posted by Rand
start car let run for 15-20s, back out of garage, sit there 15-30s while I wait on traffic, adjust radio etc.. drive away with light throttle.


Light throttle keeping it under 2000-2500 RPM ...I do the same thing at first.
 
Originally Posted by TheLawnRanger
I wait. I think it was beneficial years ago but not as much now. My vehicles seem to run better if I wait but that may just be me.


Out of all my vehicles, my '08 550i is the one that takes the longest to settle down...about 10-15 seconds. I'm on my way as soon as the RPMs drop.
 
I usually start it up, put on seat belt, adjust audio system, set up navigation and then by that time the revs have dropped. I believe part of the reason for the higher revs is for emissions related purposes, gets out of the cold loop sooner. Transmission also tends to clunk when you put in it gear when it's revving up so it's just smoother to wait a couple seconds for it to drop.
 
Lately I have not been. I've never been one to let it idle for long, only if it had problems running (back in the carb days). I haven't noticed it clunk very much either, despite high rev's, maybe the transmission hasn't really pumped up yet if I'm fast enough.
 
The Rat goes from cold been sitting for 2 wks to 1500 rpm. The push rods make a racket. It isnt so bad now I run around in low range only with the hubs unlocked. But I would have to wait until the idle dropped to 700 RPM to take off when going out of the yard. Camrys just start and go except when clearing snow. By the time I've defrosted a car, I can take off my jacket and drive in my shirtsleeves
grin2.gif
 
Pretty sure all my cars take 10-15 seconds to settle down to a normal idle after being started. I make a conscious effort to avoid shifting until RPM is at 1000 or less, but often times I don't wait if I'm in a hurry.
 
Originally Posted by TXCarGeek
I'm unsure what prompted me to do this, but do any of y'all wait for the RPMs to settle after a cold start before shifting into gear?

What's the precise reason for the higher revs to begin with? And is it at all beneficial to allow the engine to settle down like I have a tendency of doing?


Curious how old you are? Carburetored engines would close the choke and run very rich with high rpms until the engine warmed up. Back in the day, we might wait a little bit for the engine to warm up and we'd blip and gas pedal and get the rpms to settle down. Engines could be a little finicky when cold. Today computers control all that and I just get in and go.
 
It depends on how the vehicle reacts when you shift it into gear. My previous VW Rabbit with a 6 speed automatic would slam into gear somewhat if I didn't let the RPMs slow down first. But my current GTI engages gently with its 7 speed DSG. I don't have any evidence that the Rabbit was harmed in any way by not waiting ( I didn't always wait) because it was working fine when I sold it with 50K miles when I bought the GTI.
 
Originally Posted by 2010Civic
With a manual transmission I don't mind as much taking off with the revs up.


^^This.

But with an automatic,I don't like feeling the jolt when you shift in into D or R while the freshly started engine is revving high.
 
I let it settle down. Takes maybe 10 seconds in the Genesis unless it's already warm out. Same with the Camry. My Jeep doesn't have a high idle on cold start but I still wait 10 seconds or so.
 
At temps around 32 there is no reason to let a car idle at all.
If it is say 5 degrees below it I might let it idle 15 second or so...you are actually causing more wear on an engine if you let a car idle from freezing temps for many minutes.
Old unnecessary habits die hard or not at all.
lol.gif
 
Yeah … based on the oil pressure looks like the variable speed pump is putting out max per rev … I tend to get settled in while it goes through this phase.
 
I have a Hyundai 1.6T that puts out 17 lbs boost at 1,450 rpm. Hyundai "can" have issues with pistons with their short skirts and piston knock/rocking early on, besides other issue I won't go into here. I let the car idle for 1 -2 minutes in the summer and 3-4 minutes in the winter to let the pistons expand somewhat before seeing those boost levels. I know load/throttle position have a large factor, but better to let a little expansion happen, then not.
 
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