hey everyone,
i was just wondering what you guys think about engine warm ups? ever since i can remember, i've been warming up my car before leaving for school, work, or after it's been sitting around for a while. i was curious as to what you guys think about this. i usually let the car idle until it's almost at the normal engine operating level. some of my friends just run their cars hard after they've been sitting in the cold, without warming it up and they tell me that their cars are just fine. please lemme know what you think about this subject. is it a myth or fact that if you warm up your car, your engine will have a better/longer life? just wondering. thanks.

 

I usually will just wait a minute or so, until I know oil is flowing for a bit, and then go. I may be wrong but I think you'd want to get the oil pressure up quickly giving the engine a nice dose. I wont push the car until it is up to temp.

 

With modern day, multi-grade oils, you do not need to warm up the car before you DRIVE it, except in extremely cold (sub-zero) conditions. Even then, a very brief warm-up (a minute or so) is probably enough. However, it's probably a real bad idea to run it hard, accelerate to redline, etc. until it has reached operating temperatures.

 

I idle until the needle hits the bottom of the "C" line on the temp. gauge. Then, by the time I get to the corner (1/8 mile), the car is at normal operating temperature.

This takes, on average, 3-4 minutes.

 

My idiot friends do that too and its really terrible. (notice the keyword: idiot)

Cold engine oil doesn't perform as well as it would at operating temperature. That fact alone should deter someone from going crazy on a cold engine.

As for "warming" up the engine, I don't bother with that except during the Chicago winters. The engine shouldn't take much of a pounding as long as you let it idle for a minute and then drive very conservatively until a couple minutes after the oil pressure and engine coolant temp reach operating levels.

My idiot friends will fire up a cold engine and then floor it out of their parking space. Can you believe that? I cringe everytime they do that. One of my friends has a very new car and its not showing any real wear yet, despite the abuse. However, my other friend has a car that is really ragged-out. His years of abuse have left him with a poorly running engine even after a tune-up. Its a testament to the engine that its still running, IMO.

 

Sitting there at idle waiting for the engine to warm up is a waste of gas. Let it idle until the oil pressure is up then drive easily until proper temp.

 

Can't remember where I heard it but I've been following it for years...

Engine only needs about 30 seconds of warmup for the oil to cover the important bits.... esp with the 5W40 oil... starts moving quick, even under cold conditions... (I'm in Canada, eh!)

Followed this 30 sec rule b/f getting the car moving.... in neutral is a good idea as well if you have the A/T...

In cold weather, don't gun the engine until you can feel warm air coming out of the vents....

Cheers!

 

Obviously running the car hard when the car isn't at normal operating temp. isn't a great idea. I also don't think it is great idea to let it sit running until it warms up totally either. Let it run for a minute or two then get the engine/oil going.

 

Eaglerock,
Being in Southern California does make a difference. 30 to 60 seconds max and then hit the road. Good judgment and common sense dicates moderation within the first couple of minutes of operating though.

 

I heard it with my '98 Pathfinder owners manual, which I've followed for 50K and it runs, in fact it runs great. Using Syntec now since ~25K.

Since the engine is expected to gain hp over time because of wear-in aren't people delaying that gain by switching to synthetic so early? I can see changing at 10-15k , but I think 500-5k is too aggressive.

 

I let it idle for 30 seconds to about a minute to make sure we have good oil pressure and things are smooth.

It doesn't get too cold here so I don't have to worry about subzero temps.

Otherwise, I don't drive it hard until it's up to nominal operating temp. (and then some, because I think engine temp warms up more quickly than the tranny/differential)

 

I think the catalytic convertor also needs to be brought to operating temp for it to work effectively.

I've noticed in my friend's VR6, the engines runs at a slightly higher RPM when a cold engine is started, and after about 30sec the RPM drops. I've taken this to mean that the onboard computer decides that after about 30sec or so that everything is at operating temp.

Doesn't the current M3 contain some lights/indicators which go out after the engine reaches operating tempreature ?