So since it's been cold this last month or so, i've noticed what I percieve to be a quiet "Knocking" when I warm up my car in the morning.

I mostly hear it when I'm warming my car up before school. It only happens somewhere between 1000-1700 rpms, when I press on the accelerater, it smoothes out and goes away.

Has anyone else noticed this?

 

i kinda get it too

 

Is it an actual 'knocking' sound, or more of a valvetrain clattering sound? Don't rev your engine too much when cold - cold start oil pressure will exceed the pressure relief valve built into the oil filter and go to the bearings unfiltered.

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0==WW==0
"…axles of evil…" - george w. bush

 

Maybe it is more of of a clattering, I dunno. So, how long should one let it the car idle until the oil is at the optimum temp.?

 

Don't idle it, that will just burn gas. Just drive conservatively for the first 2-3 minutes. When your coolant temp gauge is at its normal position (just below halfway up) then your oil is warm enough to give the car some gas.

 

^^^
meilers' is the preferred warm-up method for any vehicle. Driving it easy for the first few minutes puts a light load on the drivetrain and warms up everything from the engine to the tranny to the rear diff, which minimizes warm-up time and wear. Cold-starts cause more wear than almost anything else short of a track day on a road course because of the increased friction when the oil is not yet up to operating temp. The ECU will also initiate a richer mixture on cold-starts which tends to wash the lubricating oil from the cylinder walls.

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0==WW==0
"…axles of evil…" - george w. bush