UpSideDown

That seems to be a reasonable explanation of this behavior. And yes this happens in 5th and even 4th gear as well. However, this seems only happen when it is cold out side and the engine is cold. When the engine temp reaches the optimal temperature all goes back to normal, the transmission/engine stops doing this. The car is from 2012, I think it starts doing this for a year ago or so. Is this a sign that something needs to be replaced down the road? Or should I take easy on this? I'm planning to keep the car few more years.

I'm having this annoying problem with my IS250 from 2012. When I'm cruising on highway gentely accelerate and lift the foot off the gas pedal, the engine rev dips briefly and comes back. It feels like a very brief engine brake. This seems happens only before the engine is fully warmed up and in any gear. Anyone know why it does this? :uh:Here is a recording of this strange behaviourhttps://youtu.be/aJCsd3QMMuY

Yeah, thats cam gear rattles. But that only happens on start up of the car.

The car seems perform normal. Rpm is steady and exhaust is normal too. It's just the injector sound come and goes. And this happens when idle rpm settles after a cold start and when the car is stationary.

Well it's not the *tick tick* noise that's bother me, I'm used to it (it's not loud when the bonnet is closed). If you listen carefully you can hear the tick tick noise interrupts and then continues. It has never sound like this before. It's very noticeable when you stand close to the car. Don't know if I should be worried.

Hey guys, see attached recorded video. anyone know why the injectors sound like this? The ticking noise interrupts here and there. It starts sound like this passed few days. The car run normal. Should I worry about it? The car is a 2012 IS250 fsport. My dealer replaced knocking cam gears a year ago.