a few months ago i began observing a crunch/cracking type of noise when i start the engine. that's the best way to describe it, but it's a high pitched sound that lasts a split second before going away. does anyone have any idea what this could be based on my bad description?

otherwise the car drives normally as it used to. i bought the car used, used conventional oil the first oil change, then mobil1 synth 5w-30 the next two, and even a toyota factory filter the last time. now has 47k or so miles on it.

 

sounds like you got the cam gear problem

https://www.clublexus.com/forums/gs-...-start-up.html

 

What year is your car? I think the TSB is for 2007 only?

 

my 2006 GS, and friends IS350 does the same thing, I think its a common and known issue? What I've noticed is it does it more frequently when there's old oil in the car

 

interesting. mine is 2006 awd. so what is this commonly known issue? do i need to get it fixed?

 

Yes I would, I just called my lexus dealer and told them that I'm having this issue more frequently show them the video that rjacket has posted http://www.youtube.com/watch?v=pBsVe...layer_embedded that might help

 

Oooh that doesn't sound right at all!

 

My 2007 GS350 had the same engine start up noise issue, dealer replaced actuators and that solved the problem.
Good luck.

 

"powertrain warranty or regular warranty?"

 

I have a 2006 3gs went to lexus showed them the video and they replaced the cam gears??!?!? HOpe the problem is solved!