Razor

Why does my accord feel slower than normal when the car has not reached normal operating temperature? does the ECU put the car in safe mode until it reaches normal temps or is it just b/c the car doesn't have enough oil pressure and makes the car feel sluggish. btw, i normally turn on my car and let it idle for 3-5 minutes but sometimes i cant wait that long(emergencies).

also, what is a good rpm max limit to rev it up to before the car hasn't warmed up fully? does 3k sound good or is that too high?

SOHCArchangel

you are supposed to wait to reach operating temps, and yes the ecu will not engage vtec and other things, personally i wait , nad if i have to go i dont shift over 3k if its not up to temp, thats just asking to be clowned.

4doorH22

You can drive the car strait after startup. Oil pressure reaches normal in the same amount of time it takes to put on your seatbelt. But, yeah, keeping it under 3,000 RPM until your temp gauge reaches normal is a good idea.

CardDealer

The combustion engine is at it's lowest efficiency when the engine is cold. At least this is what they said in my mechanical engineering class.

CmptchAV6

The engine isnt running at peak efficiency when it is cold for many reasons. Alot of the sensors are not as efficient when they are cold, the oil is not at a proper temperature for full lubrication and many other things.

4doorH22

Ummm and metal, like everything else, expands when heated. Engine tolerances are designed with this in mind. Tolerances are tightest when everything is up to temp.

CmptchAV6

yeah that was one of the many other things

p0pe

what are the long term consequences of starting cold? Will you eventually develope engine knock/ticking? It seems like if I'm in a hurry and don't let my engine warm properly (I still don't rev over 3000) my engine will sound like its running crappy.

4doorH22

No problem. Just don't get in any races until the motor is warmed up.

zeta_msz_006

Actually warming the car that long is bad for it, it's better to warm it up for about a minute, then drive off but keeping it under 3000RPM till the temperature is up to normal.

SOHCArchangel

this makes no sense, there is no difference between the two except for the second is under load

Gennady

You must also keep in mind the serpentine belt and other belts. They are rubber, and when rubber is cold, it doesnt flex or stretch as well as when it is warm. So if load is put onto cold rubber, it developes microfractures and eventually will brake. Driving off while your car is cold just unecessarily decreases the life of your entire engine.

SOHCArchangel

it has to be winter cold for this to happen, but it can and it will

and since this guy is in canada.........

Gennady

Goddamn Mexicans.

4doorH22

Is this your own theory, or did you hear this somewhere?

Gennady

I know this. Cars that are started cold and driven off right away commonly have torn belts. This is what my mechanics have said to me. No offense to any chicks, but this is usually the problem with cars driven by women.