hey guys my search doesnt seem to turn up anything for these two problems but i have two weird problems that have started up over this past winter season. the first one is when i first start my car it'll rev up to about 1200 then die down to 200rpm then bounce back up to 1200 then bounce back to 200rpm and then even out. sometimes while doing this it will stall out. This only happens when the engine is cold in cold weather. The other problem is when i first start my car i hear a weird hum for about 2-3 seconds and it will go away. i was thinking it was my belt tensioner, but my coworker things it the timing chain guides. the engine has 175k on it and it has the original belt tensior pulley as far as i know and the original timing chain as far as i know.

when the weather it warm i have none of thee issues.

 

Clean the throttle body and IACV.
Check the CTS, make sure it's within spec when it's cold.

The hum goes away after 2-3 seconds - leave it alone.

 

ok thanks


so what is the hum exactly lol, is it a common thing?