Okay someone from this thread
https://honda-tech.com/zerothread?id=431964
said that warming up your car is "bad. Its been proven bad. Just start and go, dont go over 4k rpm until the engine is warm." Can anybody shed some light on this? I have never heard of this before. How can warming up your car be bad? I always thought that driving without warming up your car is really bad because you might not get enough oil pressure among other things. I never drive my car until it goes under 1000rpm.

And yes I'm a newbie and I've done a search and can't come up with anything.


[Modified by chopsgsr, 10:19 AM 3/4/2003]

 

I think thats crap, I wait a least 30 secounds before I drive in cold weather.

 

For turbo cars, I know warming and cooling your engine are a priority. I let my turbo gsr warm up for a good 5 minutes.

 

It is essentially true. The fuel mixture on startup is super-rich - a lot condenses out on the cold cylinder walls, and the mixture would not fire if it were other wise. The condensed fuel drains past the rings into the crankcase, diluting the oil and, if it stays there, eventually breaking down to form an acid.

The longer you 'warm up' sitting idle, the longer the walls remain cold - up to about a minute. If you drive off as soon as the oil pressure lamp goes off, the engine will heat up faster, re-evaporating most of the fuel in a half hour or so of driving. It then gets sucked back to the intake via the breather and PCV valve.
Since cold engine tolerances are not conducive to aggressive driving, just drive mellow until the temp gauge rises to normal.

The worst combination, though is a long warm-up followed by a brief drive. If you drive will be 20 mi. on the freeway, then the only downside to a long warmup is wasted gas and a lot of exhaust sitting around your house. There is no benefit.

Steve

 

Good information Steve...

 

It's nice when somebody gives an informative answer.

 

sounds good and all... but isnt the main reason to warm your car, is to "warm up" all the oils and parts.. so that it prevents cracks and breakage on the initial drive during cold weahter?? cus if you drive on a cold engine.... oil temp will be low and the solidity of the oil will be sluggish.. therefore it must be "warmed up" before operating...

otherwise.. BMWs wouldnt have a oil press/temp gauge on its tac.... and it doesnt suggest that a car moves when the oil warning lights are still glowing on the tac.....

thats just my opinon... but your answer seems reasonable.

 

It sounds like a "damned if you do, damned if you don't" situation. Warming up the oil helps lubrication and prevents wear, but apparently unburned fuel can contaminate the oil. On the other hand, immediately driving minimizes unburned fuel contamination, but can wear the engine faster.

Would the best solution be a short warmup followed by a long enough trip to completely warm the engine?

Car engines are essentially a bunch of tradeoffs... the only way to prevent all of this is to never start the engine at all. Not a good solution for many people.

 

What you are saying is essentially true and the reason that they made multi-viscosity motor oils, i.e. 5w-30, 10w30. etc.
And that would explain why when I turn my car on and let it sit while I do a few things I always seem to burn more gas.......

 

I think the best way to avoid idling too long, but not letting it warm up enough is simple. when you start your car, just give the engine enough time to properly circulate oil throughout the engine. That way, everything is lubricated and some wear can be avoided.

 

So how long is it between the time you turn the key to when oil is pulled up from the pan all the way to the head? Is that all the time you need to wait?

I've always let my car warm up b/f taking off, that's just the way i was tought to do it. Usually it's just 10-15 secs., but on cold days i usually give it a good minute or so. Is this wrong?

 

The "short drive" side of things seems to make seince, I guess that is why you are supposed to follow the "severe driving conditions" maintinence schedule if you drive less than 5 or so miles to and from were ever it is that you are going all of the time.

 

Yes, don't just start and go in the cold. You should at least wait a few seconds, I usually say 30 secs max. When the engine is in idle, its really rich, so you are just basically just dirtying and wasting gas. The best way to warm up and engine is to wait like 30 seconds then start driving easy, shifting at 3k until the needle hits operating temperature. The thing with letting your car idle till normal temp then romping on it, is bad for your car. If you let your car sit in idle to warm up, there are certain parts of the engine that are'nt being lubricated, so the best way and fastest way to warm up the car is to drive it and shift at around 3k

 

personally i just let the car idle for 10-20 seconds and then i drive off trying to not go over 3k rpm.

here are other peoples input on an oil fourm website:

http://theoildrop.server101.com/cgi/...;f=24;t=000014

 

Very informative thread on a very little debated subject.

Although, I am now slightly confused? It seems a lot of people wait around 30sec or so and then drive at low rpm's till the enine is full warmed up. My idle doesn't drop off for atleast a minute or more depending on teh outside temp. Is it best to wait till the idle drops down to normal or not? I guess as long as one is'nt lead footing it around before it's optimal temp it should be good either way?

 

Damn....i guess instead of waiting 5minutes or more for my car to warm up, I should only do it in about 1 minute and then drive off. Of course that's going to be a hard habit to break because I'm so paranoid about hurting my car. But SBOURG does make a lot of sense if what he says is true. Hmm...Thanks for your input guys.

 

I always warm up my car b4 I go off.It may not be a good idea for others but I just cant stand it when my car dies.