corradoMR2

I posted a related video in the fuel pump thread here where the high whine noise is apparent several seconds after a cold start.

Now from inside the cabin, looking at the revs, the "sewing-machine-like" whine disappears above 1200 rpm.

I'm unclear if this is normal (Atkinson cycle?) or not and would like to get a feeler on how common this is. Please vote and comment. Thanks!

Ryanmcd

1 year and 12k miles later same thing, it's called direct injection. Go to the end of the video.

Swacer

Yup, what you're hearing is normal for a DI engine.

If you put headers on, you'll hear it a bit more too.

Anyone missing port fuel injection yet?

corradoMR2

Thanks guys. What I find strange is I have never heard this on my IS 250 nor my NX both of which have DI. Is it because of having more cylinders and larger displacement, it's heard?

Ryanmcd

My guess would be 4 vs 8 and also this car uses a lot more fuel. I am sure in the design that this was not an issue and may have been in the other cars just like this car makes more noise overall vs anything else Lexus puts out.

RCFormante

iTrader: (1)

Sigh...the engine in the RCF has both port and direct injection sir and the carbon buildup is pretty much minimal to none existent because of the utilization of both port and direct injection.

corradoMR2

Another minor detail I forgot to mention is the whine is only heard between 500 rpm and 1200 rpm.

In short, if everyone else hears this, then I'm good with this and probably not even worth mentioning it at my next servicing.

Swacer

Ah, that's true, I forgot it was dual cycle like my NX was.

Nothing to sigh about....