No he said LOWER rpm in a HIGHER gear.

For my S2k, I'm told by our Tech who drives the same car to idle it to "2 bars" then drive off slowly.

my bad , read it the opposite

Can you explain this all in more detail, or point to where this information is coming from? I think I must be missing something here as this doesn’t make any sense to me at all.

1)The idea that condensation builds and then somehow lingers in the cylinders, despite the explosions of air and gas, the heat from the friction of pistons moving at 1k+ rpm and the spent mix being pushed out of the cylinder when the valve opens, is something I am having a hard time with. If the motor is running correctly, any condensation that actually manages to find its way into the cylinders would be expelled almost immediately. I have seen heads get horribly pitted due to people spraying massive amounts of water into the cylinders “for performance cooling”. However this is not nearly the same, and the fractional amount of water that may have found its way into the cylinders during sitting would be expelled so quickly it really shouldn’t matter. How idling would prevent this I don’t understand.

2)Anything rotating will warm up, not to mention the coolant and oil being able to circulate for a while before taking off. I understand that driving will warm this up faster, but I am still missing how warming the car up can do any damage in the first place.

The ONLY downside I can see to warming a car up is waste of gas and the effect on the environment. Both things we need to consider, but I cant get my head around this causing any type of damage to the motor.

Please explain in more detail!

Why people still do this archaic practice is completely beyond me. 2 mins a day for 4 months out of the year = 3h of idling, or about half a tank of gas. Then people do this again after they go for lunch, get off work, after dinner, after the movie.. what a waste of gas. :rolleyes:

This isn't 1970, guys.

http://oee.nrcan.gc.ca/transportatio...cts.cfm?attr=8

I NEVER warm up my car, ever. Never have, never will. Just gotta scrape the exterior glass (I just do a "band" around my car at eye level, I'm lazy ;)) and keep a rag inside the glove box to wipe the inside of the windshield when it fogs up during the first minute or 2 of driving. And it's common sense to be gentle on your engine when it's not warmed up yet; anyone who's not a retard with cars would know that. Unless there's some regulation I don't know about that require people to WOT it out of their driveways and in their neighbourhoods.

:lol at people who don't know glass scrapers exist. I guess some people have never set foot inside a Canadian Tire?

1. It's the prolonged time below operating temperature of the engine that causes issues of condensation. Once it's warmed up through either method, it is not a problem. Because it operates at lower-than-optimal temperature for a longer period of time, excess air in the combustion process cools the cylinder liners, resulting in incomplete combustion and condensation of unburned fuel on the cylinder walls. These deposits are eventually drawn into the engine sump where they contaminate the engine oil and reduce its effectiveness as a lubricant.

This is why it's it's common advice to change the oil more often during the winter than in summer.

2. The "damage" to the engine(I would more accurately describe it as excessive wear than 'damage') is from the info in point #1. However, other components may experience excessive wear as well if the driver drives as if the engine is warm, while all other components (hydraulic fluid, transmission fluid, differential fluid) are still cold. It would be redundant to idle-warm-up the engine for 5 minutes, only to drive gently for another 5 afterwards just to get the rest of the fluids up to temp.

I understand the theory then, not sure I buy it as factual. Do you have somewhere that’s done any testing on it that we could read up on?

my DD is a 1990 EF Dx, cable clutch and transmission. as for where the heater system connects, i don't know lol. all i know is, if i start the engine with the heat on full blast, it takes 3-5 minutes longer to warm up the engine (going by what it indicates on the cluster here) compared to when i leave it at cold. Also, if persay i turn the heater on before the engine has reached its normal running temp, the needle will go back down to cold on the cluster.

i have never seen that on any other car i've driven and i can't explain it; can someone here?

its ok half tank of gas wasted because of idling after 6 months is only $20 bux or so, for that i rather have my ass warmed up rather than freezing my balls off:D

i calculate my fuel mileage every tank of gas. i actually noticed it IMPROVED slightly rather than getting worse because of the extra idling time (6.93L/100km vs 7.00L/100km).

Ya, definitely notice my drive train when it's cold. 30 year old transmissions are a little sensitive, i take it easy when i drive off after warming the engine up. Usually don't' go past 3k or so.

I would believe this. If I remember correctly on my old car if I drove it right away when it was cold I think the AFR's read really rich until it warmed up... and that car took a while to warm up.

^ me too, after the short idling period i still drive slowly until everything has warmed up correctly.

Except during the winter most people do the warmup thing a) several times during the day, and b) for a whole lot more than 2 minutes. That's a lot of bbt $ gone.

Oh, and warm balls = lower sperm count. ;) :D

There seems to be no basis on the laws on physics and thermodynamics with those arguments, if there are, then please do explain further. I do agree that idling the engine does not warm up the transmission, and it requires driving the car to warm it up, that is a given. While i'm no expert in i.c. engines, those arguments do not support the theory that idling the engine prior to "warm up" causes damage to the engine with the mechanism you described. The adiabatic flame temperature of a combustion event is on the order of magnitude of thousands on degrees F. The combustion in an i.c. engine is far from ideal, it is not adiabatic, not complete combustion, and dissociation takes place, however, the temperature is still extremely high relative to the environment. The temperature will be what it is (depending on afr), whether the engine is warmed up will have minimal effect (relative to afr). I am not convinced the water will condense out of a vapour mixture onto a surface hotter than the mixture.

You also mentioned, and i quote "Because it operates at lower-than-optimal temperature for a longer period of time, excess air in the combustion process cools the cylinder liners, resulting in incomplete combustion and condensation of unburned fuel on the cylinder walls."

Where is this excess air coming from? Correct me if i'm wrong, but i believe most cars tend to run rich after a cold start. It it is running in closed loop, then it would be running at stoich. Even if it were true that the engine is running lean, that statement contradicts itself. Running lean will help the reaction of hydrocarbons going to carbon dioxide, with excess oxygen/nox.

^ Awesome post. If the actual technical facts or test are out there, I'd be interested in reading as well whether it confirms or debunks what I've been led to believe.

All my personal information from reading online from various non-scientific sources and hearsay from various mechanics and such where pretty much every instance says its better to not idle to operating temperature than to do so.

I'm slightly skeptical about that. I'm not sure if it warms up faster or not, but low rpm/high load operations should generally be avoided. You want stable hydrodynamic lubrication for your crank bearings. ie the 2 metal surfaces with relative velocity with each other actually floats, and are not in direct contact. For this to happen, you need enough relative velocity(engine speed). The load also can not go above the point at which the file become unstable(throttle).

I knew I wasn’t the only one who this seemed odd to.

I would say the people who have been saying this to you Sonick are either very confused, or are looking to try and have people cut down on idle time because of environmental concerns.If you are in conact with any of these folks who have told you this, try and get some actual reasoning out of them.

While I am all for cutting down on our environmental impact, I still dont think the argument being brought up with you is a factual one for causing engine damage. "Cold" is a reative term when it comes to temps inside a motor and cylinders.

True, perhaps the technical reasoning behind the actual excessive engine wear claims are sketchy, but overall I still believe the action of not idling to operating temp is still better than doing so because of the the warm-up of other components and such. Either way, I am interested in hearing about it if anybody finds any hard facts.

If there's technical information out there that suggests idling to temp is BETTER than not idling and driving gently, I'd be glad to hear it and apologize for giving bad advice.

Personally I really think about the environmental impact, just whatever is best for the car lol.

The discussion in here is very interesting.

It'd be interesting to see a comparison of two cars over a lifetime, one always warmed up slowly, one driven right away, both driven similarly.

It's possible that there wouldn't be any difference in engine longevity at all, given the cold car wasn't redlined constantly, when completely cold.

You did bring up a valid point about warming up other components such as the drivetrain. A lot of people only warm up their engine, then proceed to driving the car normally. Personally, I warm up the engine by idling AND i take it easy once i start driving.

As for the environmental impact, and wallet impact, I think it's actually debatable. There's no doubt that idling the car results in an overall efficiency of 0%, or 0 mpg. But the efficiency of the engine itself is actually quite good, especially in newer cars. It consumes very little gas, and produce very little harmful gases. With that in mind, what if we look at the grand scheme of things. If a car was never allowed to warm up in its lifetime, maybe the engine will fail sooner compared to a car that had always been warmed up on a cold start. What is the total environmental impact of each car? Dos scrapping car A earlier (making the owner buy another car earlier), have a greater or less environmental impact than the total amount of time car B spent in idling? How does the amount of money needed to repair the engine in car A(or amount of money to buy a new car), compare to the extra gas bill that went into idling car B?

There are really no right answers to those questions, it depends on the car, and it depends on you ask. Just something to ponder about. On a side note, from manufacturing to scrapping, a Prius has about the same environmental impact as a Hummer. (quoted from an old professor/engineer, I can not confirm the validity of this statement) The point is, we have to think about the environment impact as a whole, not just at specific stages of a product's life.

My car doesn't move unless it's been warmed up. The engine will stall continuously. Yay for old rotaries.

lol freaking ED u sure knows a lot about sperm loss eh

:p;):haha::haha::haha::haha::thumbsup:

You betcha. Why, you only know about sperm gain? ;) :p

:haha::haha::haha: lol wtf dude ahahaha

ic wat u did there


Siemens taught u about semens