i always just jump in and go , but then again i live in phoenix so it not cold cold cold lol, I do hear spark knock on startup though which is normal, go's away after it warms up alittle, my 93 s10 blazer did the same thing, doesn't hurt anything.

 

Interesting article...I haven't been warming mine but it was more out of consideration to the neighbors as I leave for work at about 530 am...I have been worried about not warming the motor causing problems though...now I know I don't need to worry...bad feelings gone

 

I agree with most of what that article says. Not this though: "idling forces an engine to operate in a very inefficient and gasoline-rich mode." I don't think so, especially with a computer-controlled, fuel injected, O2 sensor-equipped engine. The injection system will adjust the air:fuel ratio to stoichiometric at idle just as well as it will at elevated engine speeds.

One thing I *don't* see addressed in the article is an important point to me: engines with flat tappets (think 3.4 V6) rely on oil being flung from the crankshaft journals to lube the cam lobes. Low engine speed means less oil whech can cause problems. This is why a newly rebuilt engine should *never* be started and run at idle for any period of time. You start it and raise the RPMs to 2000 or so and that gets enough oil thrown off the crankshaft to lube the cam journals.
It's also why I use the ZDDPlus oil additive in all my flat tappet engines, old or new.

 

not sure on the ls motor but the lt1 fuel injection system runs on a set program (open loop) that does not depend on the readings from the 02 sensors so the motor does run rich till the 02 sensors warm up.

 

Even if you "warm" the engine, don't forget about other cold fluids. Power steering, automatic, differential tranfer case and then there's steel. Craby's right, take it easy until everything gets up to temp or loosened back up. My Z71 shifts stiff and makes all kinds of noises, moans and groans, until I've driven about 3-4 miles, then settles down and all is well. BTW it was 12 here this morning, she was not a happy camper for the first few miles.

 

haha same here, stiff shifts is a pain. but then again my car is what I call, random or does what it does when it wants. Sometimes ill drive for 20 mins. and still have stiff shifts and other times the shifts are loose and easy.

 

Half the reason for letting a car "warm up" is to allow the oil to reach the proper viscosity to allow necessary lubrication. Thick (cold) oil does not do the best job getting into bearings and flowing through oil passages. While letting the engine idle for a few minutes will use more gas, I am of the opinion that a little gas over time is less costly than an engine overhaul due to unnecessary wear.

 

does anyone really not have 5 min to let their car warm up? why wouldnt you, if it doesnt hurt, and kinda helps, isnt it a no brainer? just seems dumb to me, in the summer do i sit there for five min, no but im def not gunna be hard on it for a few

 

did you guys read the article? there is a reason for multi viscosity oil, i believe cold starts have something to do with it. the oil is thinner when its cold. as far as letting it set and idle i do it in the winter so the dang car is not so cold but its not good for the motor.

 

Not quite so... Multi viscosity oils have better low temperature properties than a straight weight oil, but they still do thicken up when its cold. Ever try pouring cold oil? It comes out fairly thick. Then compare that to doing an oil change when the motor is still hot, the oil pours out like water.

Its truly best to avoid hard driving until the oil is up to operating temperature.