by dracodoc, December 27, 2004
Today I lost my key in my corolla with engine running. We got the lock service after 4 hours...(1 hour of shopping for I didn't know it, 3 hours of call and wait )
So the engine idled for about 4 hours, I know that is not good for engine, but how much? My last oil change was 2000 miles before, maybe I should change oil soon?
Other than the wasted fuel, I cannot think of any damage that would have been done to the engine outside of normal wear and tear. If you have not noticed any performance problems after the extended idling period, then I wouldn't worry about. In a perfect world, you would add that idling time to the total hours on the engine between oil changes, but that would be a bit difficult to factor in. You say you have 2,000 miles since your last oil change, just do your next one about 200 miles sooner and you should be about right.
The only potentially problematic issue after such a lengthy period of idling might be condensation. If ambient temps are cold and/or humidity is high, condensed moisture can accumulate in oil that hasn't been sufficiently heated to allow moisture to boil off and dissipate.
This can created higher than normal acids accumulation (products of combustion), and tends to speed up internal corrosion. Enough of that can cause damage over time.
I would suggest taking the car out for a good highway run of at least an hour, and most of any accumulated moisture will evaporate. If this isn't possible, warm up the engine and get the oil changed if you are concerned about the situation.
Dai_Shan
So when you hear the common statement of..."Don't warmup your car in the winter for more then a few minutes"
They are just refering to loss of fuel ?
Seems to me there is usually a certain hint of "its bad for your car" kinda thing...if they are just refering to adding unnessesary run-time...they should be kicked...(whats a few minutes gonna hurt.. ::shakes head:: )
4 hour seems to be enough to warm the oil and a parking lot... I do not see how condensation can form in hot oil. You may see condensation on outter wall of crankcase where there is a barrier beetwen hot and cold surface (dew point). And this is gonna be only for short period of time, cause your engine will warm the area around the car in 1 city block.The only potentially problematic issue after such a lengthy period of idling might be condensation. If ambient temps are cold and/or humidity is high, condensed moisture can accumulate in oil that hasn't been sufficiently heated to allow moisture to boil off and dissipate.This can created higher than normal acids accumulation (products of combustion), and tends to speed up internal corrosion. Enough of that can cause damage over time.
I would suggest taking the car out for a good highway run of at least an hour, and most of any accumulated moisture will evaporate. If this isn't possible, warm up the engine and get the oil changed if you are concerned about the situation.
My uncle did the same on his Camry. No worries
If any problems could occur as a result of idling your car for 4 hours, I strongly doubt that condensation is one of them. I'd say having the thing stolen would be the primary concern. The engine is already running; all a thief would have to have done was to put a brick thru a side window, open up, get in, and drive away!
Like I said, change your oil and filter a couple of hundred miles earlier, and don't worry about it.
yeh i really don't think that will harm it at all, i mean if you were driving a highly modified car and you were running it rich for certain reasons then i might consider checking the plugs and stuff for fouling, but not likely to happen on such a new car with no internal engine mods....ive heard of old cars that are carbd getting preatty gummed up from that, but on further inspection it turns out that the car was left to idle for days on end (to avoid cold starts) which is ridiculous if you ask me.
I've left my 95 Corolla idling for about 6 hours inside a building of a carshow, and no damage at all. Also, barely lost any fuel according to the guage, which doesn't make a lot of sense, but I'm not complaining.
Get spare keys made, and don't store them inside the car. Having an AAA membership helps too, as that's a covered service. It only had to happen to us once after I rectified the problem by paying the locksmith $50 for a job that took him less than five minutes.
After that long time idle, we drove to home, that's an 1 hour highway on 70 mphThe only potentially problematic issue after such a lengthy period of idling might be condensation. If ambient temps are cold and/or humidity is high, condensed moisture can accumulate in oil that hasn't been sufficiently heated to allow moisture to boil off and dissipate.This can created higher than normal acids accumulation (products of combustion), and tends to speed up internal corrosion. Enough of that can cause damage over time.
I would suggest taking the car out for a good highway run of at least an hour, and most of any accumulated moisture will evaporate. If this isn't possible, warm up the engine and get the oil changed if you are concerned about the situation.
we have spare key but left it in home. We have a AAA plus membership, but called the local AAA service center serveral time ,no body picked up the phone. At last we called locksmith and paid $40. The work took him 1 minute, while the paperwork took him 5 minutes. With their tools, it seemed so easy!!Get spare keys made, and don't store them inside the car. Having an AAA membership helps too, as that's a covered service. It only had to happen to us once after I rectified the problem by paying the locksmith $50 for a job that took him less than five minutes.
I found AAA manual said you can ask reimbursement for this, I will try to apply it.
Thanks for you all, your advice made me feel much better.
It's just operating hours. 4 hours idling is not much different as 4 hours driving on the freeway to an engine with modern computer system that keep the engine running lean.
At work, several of the vehicles used by our maintenance crew are left running almost 24/7 in the winter. Some of these are 15 year old chevy suburbans and others are small kawasaki ATV type vehicles.
Bottom line... don't worry about it.
Condensation in internal combustion engines can and does happen, in spite of the naysayers who insist it doesn't.
Water, plus combustion byproducts(most of which is CO2)=rust and corrosion.
If oil temps don't get above the boiling point of water, accumulated moisture won't be dispersed--idling for long periods in cool or cold weather is the ideal situation for this to happen.
Don't believe me?
Remove a valve cover and take a look at what's inside, after a short run,long idling period,or just after engine is started!
You're in for a surprise.
You will immediately note condensed moisture, plus often see rust and corrosion that's on internals--especially if your driving habits are as described earlier.
Better still, just remove the oil filler cap--what do you suppose that accumulated whitish goop around the rim is?
Check it out.
Having said all that, the situation described at the beginning, if it's an isolated case, shouldn't be a problem for the owner.
But don't ever discount the long term effect of condensed moisture in an internal combusion engine!!
Again explain me how condesation condition still exist on long idling engine.Condensation in internal combustion engines can and does happen, in spite of the naysayers who insist it doesn't.Water, plus combustion byproducts(most of which is CO2)=rust and corrosion.
If oil temps don't get above the boiling point of water, accumulated moisture won't be dispersed--idling for long periods in cool or cold weather is the ideal situation for this to happen.
Don't believe me?
Remove a valve cover and take a look at what's inside, after a short run,long idling period,or just after engine is started!
You're in for a surprise.
You will immediately note condensed moisture, plus often see rust and corrosion that's on internals--especially if your driving habits are as described earlier.
Better still, just remove the oil filler cap--what do you suppose that accumulated whitish goop around the rim is?
Check it out.
Having said all that, the situation described at the beginning, if it's an isolated case, shouldn't be a problem for the owner.
But don't ever discount the long term effect of condensed moisture in an internal combusion engine!!
No question on short idle.
Obviously it's just a waste of time to attempt to convince anyone who doesn't want to be convinced.
Those who believe they're always right will never admit being wrong.
I'm sure there are more worthwhile issues to argue about anyway.
So let's just move on.
Don't believe me?
Remove a valve cover and take a look at what's inside, after a short run,long idling period,or just after engine is started!
You're in for a surprise.
You will immediately note condensed moisture, plus often see rust and corrosion that's on internals--especially if your driving habits are as described earlier.
Rust on all-aluminum engine? Rust on internal parts with the thin layer of oil on them?
Come on..
Still not convinced
Happy New Year
Ti-Jean
When I worked at James Bay, about 20-25 years ago, most vehicles were left idling for hours, even days, as you describe, But some GM V8's didn't like the treatment very much; I happenend to be at the garage once when a mechanic showed me a camshaft he had just pulled from a pick-up or Suburban that had no more lobes where several used to be.At work, several of the vehicles used by our maintenance crew are left running almost 24/7 in the winter. Some of these are 15 year old chevy suburbans and others are small kawasaki ATV type vehicles.
Bad lubrication, but extreme conditions.
on the oil rigs here most of the guys leave their diesel trucks running 24/7 cause if they shut them off they will not start again cause its so damn cold (-20 f)
Gee I hope idling doesn't cause damage. We spend half our time here in Southern California waiting through lights and sitting in traffic jams, all in idle. 
OUKB, It doesn't concern me one whit that you are "unconvinced." You are free to remain that way for as long as you like, as far as I'm concerned. Your disbelief in what is a well known fact, as I've already stated, isn't worth arguing about.
To the others who have commented on the issue of condensation and possible corrosion as a result..........
Camshafts are the most vulnerable to corrosion, to a lesser degree are valves, valve guides, crankshafts, bearing caps, pushrods , lifters, rocker arms (latter three items in pushrod designs), and any steel or ferrous engine components.
Note that I'm not saying it happens in an isolated instance of engine idling for long periods--in the first posters situation, chances are there will be no problems at all.
Some have said diesel engines don't have problems and idle for long periods. Correct, but why? Diesels are hot running engines all the time--heat is what ignites the combustion process in a diesel--heat from extremely high compression. Any resident moisture in a diesel engine won't be there for long!
Where condensation is most likely to be a factor is in cold and damp weather, and when engines frequently haven't been run under load to disperse any residual moisture through evaporation--- because oil temps have been allowed to consistently remain below the boiling point of water.
Those who live in warmer climates (southern Calif. for example) are less prone to the problem than those who live, say, in Northern US or Canada.
It will eventually eat up certain engine components though corrosion.
A camshaft that's been scored, pitted, or worn down through corrosion isn't a pretty sight.
Nor is the cost to replace it.
Originally posted by Veritas:
You didn't answer his question. And your sarcasm doesn't make your case any more credible.Obviously it's just a waste of time to attempt to convince anyone who doesn't want to be convinced.Those who believe they're always right will never admit being wrong.
I'm sure there are more worthwhile issues to argue about anyway.
So let's just move on.
Slalom, I ****ure you I am always willing to respond to legitimate and sincere questions.
Please note my response above and before your post, to legitimate, and I believe sincere, questions raised by others.
OUKB's post, and I suspect yours, weren't legitimate questions, they (OUKB's especially) seemed more like taunts. They sure aren't sincere.
I don't consider taunts, nor the petty attitudes accompanying them, of any concern to the issue being discussed, thus I choose to ignore them and move on.
I suggest you do the same.
On another website, there is a poster that has both an oil and coolant temp gauge. He indicated that at idle, his oil leveled off at 235F and his coolant at 218F. I've popped my hood open on several occasions when it was raining, and when the raindrops hit the head cover, they boil right off. This tells me that the temp is well in excess of 212F.
Veritas: You are throwing around a lot of sarcasm and misinformation. Please post facts and/or links to credible information to make your case, or the rest of us have to assume that your belief on condensation in an idling engine is nothing more than your personal opinion.
Slalom, my comments/advice to OUKB and yourself--and my knowledge about condensation and its effects--remain unchanged!
I've taken apart and seen too many corrosion damaged engines, and know better than to deny its existence.
Feel free call it what you wish--opinion, sarcasm, or whatever, it makes no difference to me, and I'm sure "the rest of us" (whoever the "rest of us" is--do you really speak for everyone here?).
When you've seen what I have, you might remember this discussion.
If you want links, try a Google search on "Condensation in Automobile Engines", or "Excessive Idling of Auto Engines."
Here's one of many similar comments you will find: "Can idling damage my vehicle?
YES. Excessive idling can actually damage your vehicle. The engine is not working at its peak operating temperature so fuel doesn't undergo complete combustion. This means that fuel residues and moisture are condensed and this can contaminate engine oil and damage engine parts through corrosion. Condensed moisture in the vehicle's exhaust can lead to corrosion and reduce the life of the exhaust system as well."
There are thousands of hits on this topic. When you're done reading, I would suggest at least an apology. I eagerly await one.
Bye Now. I'm outta here!
Originally posted by Veritas:
Apologize for what? Calling you sarcastic? Stating that you post misinformation?I did a google search, and guess what? I found dozens upon dozens of credible websites that talk about the subject, but not one of them says anything about moisture condensation in the engine. They talk about fuel condensation on the cylinder walls and moisture condensation in the exhaust system, but not water condensation in the engine.If you want links, try a Google search on "Condensation in Automobile Engines."There are around 40,000 of them. when you're done reading, I would suggest at least an apology.
Here is an example of what many of them say: http://www.ercsv.org/ERCNews%20fall%20032.pdf
Since several of us have repeatedly asked you to post facts - not opinions - and/or links to support your claims and you have not, we can only assume that you are incapable of providing this information.
