First, I smell a whiff of coolant like a head gasket is blown when the car is first turned on, especially if i reverse out of my parking spot. This issue has been around for about a year and my coolant levels are really stable and i haven't noticed the coolant reservoir levels drop in a year. I have no trace of coolant in my oil, the car isn't overheating either. Not sure what this could be.

FYI i have a sc300

Also, this issue has been going on for about a year now (not sure if it's related) but it got worse last winter. On a cold start i'll hear a what sounds like two metal plates grinding and chattering from 0-500 RPM's as the motor initially revs to 2k and idles down with warm up. Above 500RPM the motor sounds okay, at least the problem is inaudible above 500RPM. If I let the clutch out when the engine is cold just right to get the RPM's to drop low (500ish or lower) i hear the grind sound. It doesn't sound like any of the rod knock videos on youtube and my clutch grabs just fine in all gears. Also If i've been driving for less than a half hour, blipping the gas for rev-matching downshifts causes the sound.

My MPG seems fine, I think the car warms up quicker now than it used to but it could just be a summer thing, that and i'm running 50/50 coolant instead of the toyota red stuff.

 

bump, anyone?