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

Always. Then I let it just ease off towards wherever it's going until it's at least a little warm. I came to notice how tight engines get when it's cold when I bought a Cessna. Flopping that prop by hand was a whole lot harder when it was less than 40 and felt like it was nearly seized below zero and synthetic oil wouldn't help with that. I could preheat it which loosened it up considerably which was easy with a small propane stove and flexible duct.
You can't do that with a road vehicle so I take it easy until things warm up a bit. Aluminum expands and contracts a lot more than cast iron which is what I assume caused all that drag in the continental that went fairly unnoticed with any iron block I ever manually flipped over. All those aluminum blocked cars today surely must have some Degree of that cold tightness as the Continental so I take it easy when they're cold.
 
I let the car idle for 15 to 30 seconds. My wife on the other had will start the car and shift into gear so fast. Like the car doesn't even get through the system checks and and the gauge cluster isn't even fully turned on. Once she told me that her Civic didn't move did not instantly start backing out of the garage and she thought it broke the car.
 
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Originally Posted by SHOZ
Originally Posted by Duffyjr
My Buick jumps up to around 1500rpm when it first starts but immediately drops to 1100ish and them over the next couple minutes slowly drops, at that time I engage the tranny usually around 900ish. There have been a few times I've been in a hurry and take off right away but it doesn't seem to have any adverse affect, no jerking or banging.

I wonder if he high rpm on start up has to do with getting oil going, I can imagine in my mind the pump spinning faster and pumping more oil in that small time frame but of course that's just a guess.

The high rpm on cold start is for emissions and getting the cat up to temp and into closed loop faster.

I get that when it's at 1100ish rpm's for those couple minutes but that 1500 rpm blast is only for a split second. I don't remember for sure but I don't think I've ever owned a vehicle that jumped that high at start up, it seems to do it all the time not judt on a cold start. My mech said it's normal so haven't thought to much about it.
 
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Originally Posted by Michael_P
I'm a div>


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Yes, Food for thought.
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^

I've driven manuals since the '68 Bug as my first car around 1977.
Three clutch jobs I recall since then;

* A 39,000 mile VW Fox I picked up in 1993 that went to about 185,000. I loaned it to a friend of a friend 2 different times (and friends) the last time at about 183,000, the clutch started going (or the driver burned it up ?) coming up from Raton pass in 1999 or so. The first friend / customer returned the car with burned up brakes. I had to use the e-brake to get it home.
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* 2003 Suzuki Aero I owned and gave to the kids, then they taught their friends how to drive a stick !!
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(54,000 miles if you can believe it). It was fine afterward and well into the 128,000 mile odo or beyond when it was sold.

* My 2004 G-35 coupe, picked up at 90-some ,000 miles. Clutch was likely weak by then and IMO, due to 2 previous owners. How do you know if 'they knew how to properly drive a stick ? Over 5 plus years, I added about 25,000 to the odo and started to baby the clutch as if was obviously toasting at 109,000. Those things are well known to live to 150,000 - 180,000. miles and beyond.
 
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I will always wait for the RPMs to settle down from high-idle before I take off with the car. Usually in the focus, it's once my headunit connects via BT to my phone and music starts playing (~20 seconds.) For the evo, it's by the time I finish my cigarette outside the car. Then light driving until I can feel the transmission fluid warm up.
 
With carbureted engines, I put the engine under load as soon as it would run decently---which was almost right away in warm weather.

Prius engine speed doesn't "settle." On a cold start, regardless of ambient temperature, it holds a constant 1280 RPM, until after exactly one minute it suddenly drops to zero if not under load. If you ask for moderate power before the minute is up, the system demands high current from the battery (because it's attempting to let the engine warm up with no load). Therefore, I take off as near as practical right at the end of the minute, other than initial low-speed, low-power moving out of a parking lot.
 
Originally Posted by 2010Civic
With a manual transmission I don't mind as much taking off with the revs up.


I believe that is the reason the pilot bearing failed on my Focus at 70000 miles. That car would race up to 2500-3000 RPM on cold start and stay there for 5-10 minutes on a cold morning. If I was in a hurry, I would just drive. The problem is, the engine would force itself to stay at 3000 RPM. So if I pushed in the clutch, it would race up. Every.Single.Shift. At least I could drive half way to work without touching the gas pedal.

That was also a lot of wear on the synchronizers inside the transmission, but mostly the pilot bearing and throwout bearing. That car was ridiculous with the high idle, but it had to maintain it's ULEV rating and that meant the cat had to be immediately lit off and kept to temperature.

My Forester is a lot better. It'll idle at 2000 for a few minutes, but if it senses the car starts to move, it'll drop the idle down to normal.
 
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Originally Posted by Miller88
Originally Posted by 2010Civic
With a manual transmission I don't mind as much taking off with the revs up.


I believe that is the reason the pilot bearing failed on my Focus at 70000 miles. That car would race up to 2500-3000 RPM on cold start and stay there for 5-10 minutes on a cold morning. If I was in a hurry, I would just drive. The problem is, the engine would force itself to stay at 3000 RPM. So if I pushed in the clutch, it would race up. Every.Single.Shift. At least I could drive half way to work without touching the gas pedal.

That was also a lot of wear on the synchronizers inside the transmission, but mostly the pilot bearing and throwout bearing. That car was ridiculous with the high idle, but it had to maintain it's ULEV rating and that meant the cat had to be immediately lit off and kept to temperature.

My Forester is a lot better. It'll idle at 2000 for a few minutes, but if it senses the car starts to move, it'll drop the idle down to normal.

That isn't doing the clutch disk or pressure plate any good either.
 
I FINALLY got my wife into the habit of mentally counting to 10 before engaging the transmission on a cold start. Our vehicles are in a basement garage and the temperature rarely falls below 60 degrees F so the engines settle down pretty quickly. I could see her cars front wheels shudder on cold start at high idle when she put her car in reverse on cold start.
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I usually wait around 1-2 minutes where the RPMS start to drop from initial start.
For the Cummins it settles into regular idle after starting just waiting for the air pressure to build up.
 
Well, good to know I'm not the only one. It's generally not an inconvenience to wait because I usually take that long to settle in anyway.
 
Originally Posted by Miller88
Originally Posted by 2010Civic
With a manual transmission I don't mind as much taking off with the revs up.


I believe that is the reason the pilot bearing failed on my Focus at 70000 miles. That car would race up to 2500-3000 RPM on cold start and stay there for 5-10 minutes on a cold morning. If I was in a hurry, I would just drive. The problem is, the engine would force itself to stay at 3000 RPM. So if I pushed in the clutch, it would race up. Every.Single.Shift. At least I could drive half way to work without touching the gas pedal.

That was also a lot of wear on the synchronizers inside the transmission, but mostly the pilot bearing and throwout bearing. That car was ridiculous with the high idle, but it had to maintain it's ULEV rating and that meant the cat had to be immediately lit off and kept to temperature.

My Forester is a lot better. It'll idle at 2000 for a few minutes, but if it senses the car starts to move, it'll drop the idle down to normal.


That would suck. I'm surprised anything in the mech interface lasted 70 k miles.
Nobody should feel forced or hurried to drive away with an engine racing at 2500 or more. That was a problem that should have been dropped in Ford's lap (dealership service) if it was always that way or purchased new.
With modern engines or newer cars/trucks etc... I'd consider 1500 to 1700 rpms even for a min or more to be excessive unless some particular design or manual specifies.
 
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I hate our 3.3L Sienna's cold idle, it revs waaay up (1500 to 1800rpm) and holds it there for several minutes, plus it wont shift into high gear until temp reaches a certain point.... Why do this? To fire the cat off quicker, emissions. This seems to be a common strategy for Toyota in that era. No other vehicles that I know of hold a high idle so long when cold than certain Toyotas of that era.
 
Originally Posted by Miller88


I believe that is the reason the pilot bearing failed on my Focus at 70000 miles. That car would race up to 2500-3000 RPM on cold start and stay there for 5-10 minutes on a cold morning.


Even if it was frigid that doesn't seem right. Never took it in and opened a case on it with Ford corporate? Sounds like a fault to me.
 
My remote start will reach 4 floors down through the parking garage, so I start it as I begin walking down the stairs, and it's settling to idle as I click my seat belt. I remote start it from inside the house in the morning, and it runs for 2-3 minutes while I get ready to leave. High idle is annoying with an automatic.
 
Some time spent in a car with a carburetor and manual choke can tell you a whole lot about the necessity for this

Often, with a manual choke, the first 1/3 or so of the pull doesn't do anything with the choke mechanism itself, but instead is just working the fast idle cam.

In warm weather, with the car stone-cold(not run in several hours) I usually start with the choke all the way out(fast idle+enrichment) and after starting the engine will often stall if left on full choke more than a couple of seconds. Usually, the engine will appreciate ~10 seconds of fast idle, but will often settle down to a stable idle if taken off fast in 30 seconds or so.

Cold temperatures can be a different story. I will often need to use full choke a minute or more to keep the engine running, and need the fast idle an additional minute or to keep it from stalling when stopped and the like.
 
Originally Posted by bachman
Originally Posted by Miller88
Originally Posted by 2010Civic
With a manual transmission I don't mind as much taking off with the revs up.


I believe that is the reason the pilot bearing failed on my Focus at 70000 miles. That car would race up to 2500-3000 RPM on cold start and stay there for 5-10 minutes on a cold morning. If I was in a hurry, I would just drive. The problem is, the engine would force itself to stay at 3000 RPM. So if I pushed in the clutch, it would race up. Every.Single.Shift. At least I could drive half way to work without touching the gas pedal.

That was also a lot of wear on the synchronizers inside the transmission, but mostly the pilot bearing and throwout bearing. That car was ridiculous with the high idle, but it had to maintain it's ULEV rating and that meant the cat had to be immediately lit off and kept to temperature.

My Forester is a lot better. It'll idle at 2000 for a few minutes, but if it senses the car starts to move, it'll drop the idle down to normal.


That would suck. I'm surprised anything in the mech interface lasted 70 k miles.
Nobody should feel forced or hurried to drive away with an engine racing at 2500 or more. That was a problem that should have been dropped in Ford's lap (dealership service) if it was always that way or purchased new.
With modern engines or newer cars/trucks etc... I'd consider 1500 to 1700 rpms even for a min or more to be excessive unless some particular design or manual specifies.


Yes, that Focus has a defect or issues with the idle control at cold start. Why he wouldn't complain is beyond understanding.
 
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