Accidental rev in freezing weather on cold start :-/

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=removed rich cornucopia of commentary=

No damage. Have your coffee next time before you go to the car.
 
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Originally Posted by oil_film_movies
Originally Posted by ZeeOSix
Originally Posted by SirTanon
If you had started the car with your foot on the gas, and revved it up to 4500 RPM immediately, then I might be concerned about it, but after 10 seconds of running, it's a certainty that the oil was everywhere it needed to be, and did its job.
+1 ... Not much to worry about, just don't make it a habit though.
The oil filter differential probably put a hole in the media. Maybe, among us worrying types anyway. ... If a Fram Ultra was there, they don't tear (rhymes!). If a paper element filter was in place, please don't race. (kinda like a rap song at this point....)

Yup that paper end cap flexed, saving the media from tearing
thumbsup2.gif
 
Doubt it really matters all that much if it wasn't under load and was only doing it for a split second. Cold start protection is far better today than it ever was I'd think, and as others said - after 10 seconds it's going to be oiled even near the upper limit of freezing.

Of course the craziest thing I remember doing was taking my car out at lunch from my workplace. It was this oddball setup where the lot had a short onramp to an expressway. I'm taking my '95 Integra GS-R and I see I'm going to either get hit or will need to slam on the brakes to avoid someone who didn't seem to care if I was trying to merge in or not. So I floor it all the way up to the 8000 RPM redline after less than a minute of starting my car. It didn't seem to have any after effects. I was the only owner (if you don't include my insurance company after it was stolen, recovered, and declared a total loss) so nobody else had to deal with long-term reliability.

My tendency is to drive slowly, although not typically in the temps you describe. I've driven my vehicles in temps that low, but typically with some flavor of Mobil 1, which was at least claimed to pump faster than the "conventional" equivalent. And then I usually idled just to wait for the heat.
 
Originally Posted by LeakySeals
What weight oil are you using? What filter?


Not sure. Its a BMW 2 Series - Whatever BMW service puts in it.
 
Originally Posted by ZeeOSix
Originally Posted by SirTanon
If you had started the car with your foot on the gas, and revved it up to 4500 RPM immediately, then I might be concerned about it, but after 10 seconds of running, it's a certainty that the oil was everywhere it needed to be, and did its job.


+1 ... Not much to worry about, just don't make it a habit though.


What would the difference be if doing it immediatly vs. 5-10 secs??
 
If it's cold weather then there is no need to use the gas while warming up. The general consensus is to get the oil pressure up then drive conservatively until the engine is fully warmed.

No need to overthink this.
 
The mfg test in cold weather. They have in dry frozen to -30 garage for no frost. They start car. let idle. Open door maybe 10 or 15 seconds, pull out on the heated track and then lap at wide open for a certain number of miles. This is repeated, and if damage is occurring they improve things. This is why most new cars have bypass systems so water is always circulating even when water is not going to the radiator.

Rod
 
Originally Posted by Jenson
Originally Posted by ZeeOSix
Originally Posted by SirTanon
If you had started the car with your foot on the gas, and revved it up to 4500 RPM immediately, then I might be concerned about it, but after 10 seconds of running, it's a certainty that the oil was everywhere it needed to be, and did its job.


+1 ... Not much to worry about, just don't make it a habit though.


What would the difference be if doing it immediatly vs. 5-10 secs??


Oil has flowed to parts in thr first 5~10 seconds after starting, which gives protection from wear. If it revved to 4500 RPM instantly there would be less time for oil to get to parts, and more risk of wear.
 
If one 4500RPM with no load on the engine killed it, I wouldn't buy the same one again. You have likely done zero long-term damage.
 
My sig car is limited to 4000 rpm when in neutral or park. Most modern cars are also limited. BMW used to limit them when cold as well, IIRC. My guess is you did absolutely no damage.
 
I thought that at least in the short term most oils produce some sort of sacrificial barrier that bonds to metal parts, and it will tend to reform quickly once up to normal operating temps. Of course you don't want to have this happen too often, but every ICE deals with cold starts with only residual oil and/or antiwear additive protection for a split second.

But seriously - the key is that it wasn't under load. I thought the biggest problem isn't revving it up, but dealing with higher combustion chamber pressure.

I live on a hill and can tell when my neighbors are leaving. I can literally hear them start and in less than 10 seconds they're off and revving it going uphill. Somehow their vehicles haven't died yet and don't put out oil smoke. I wouldn't do it myself, but they're doing it every day. One time certainly doesn't sound like a big deal where the revs have blipped in park or neutral.
 
My guess is first you blew a hole in your oil filter. Secondly, some of that oil filter material got lodged in your oil filter's bypass valve. Now you are running bypass the entire time with very little filtration of the engine oil taking place.
My guess is you would shorten your engine life 1 minute for every hour driven between now and the time you replace your oil and fuel filters. (This is just a rough estimate) Listen really close and you may imagine you hear
a very faint ticking noise. This ticking would verify my hypothesis.


And it's possible your spark plug holes are full of coolant due to the extreme pressure that was exhibited in the combustion chambers of #2 and #4 cylinders. Check your coolant reservoir tank level to verify any loss of coolant
before you start messing with the spark plugs.


The reality is I wouldn't worry too much at all. Everything with the engine should be fine. I'd be far more concerned about the synchronizers in the transmission. Spinning at RPM's like that below freezing temp could put too
much pressure on the throw out bearing in the passenger side CV joint. But to be honest with you, I have never seen or heard of this happening. I would say it is near impossible.

Full disclosure, I am not a mechanic but I did stay at a Holiday Express last Thursday.

Don't believe a word you just read.
 
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I would not worry about any extra wear this may have caused. I'd be more concerned about you getting the pedals mixed up. Next you may end up killing someone. If your'e getting up there in age you might consider giving up driving.
 
You have more important things to worry about I'm sure.
Our newer Forester pegs the engine at 2000 revs on start without regard to ambient temperature.
Seems a little high on a sub zero F morning, but I'm guessing that Subaru may know a bit more about engines than I do or anyone else here.
I doubt that you did any harm but I'd not make a habit of this.
Things happen and engines still lead long and healthy lives.
 
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