High pitch noise from engine. Exactly like mosquito cellphone ringtone

[scoobe]

yeah so basically when my car is idling there is a very high pitch frequency type noise. Its very similar to that ring tone on cell phones that hurts your ears if your younger. People 40 and up usually cant hear it because of how slow hearing loss is.

It sounds like its coming from right in the center of the engine. Pretty hard to locate in general.

I recently replaced the cars MBC (dont know brand) that came with the car with the stock hoses and retrictor pill. the noise was going on long before i put it back to stock. Currently its 100% stock idling at 18-20 vac and hitting full boost around 4000rpm

[infox]

not sure what it is but I had the same thing on my 03 legacy l, you could only hear it if you were outside the car. Spoke to a few dealers and they said its normal?

[Timdog1650]

I wish I had a better answer, but I get it too. As long as the car drives/performs properly, I would not suspect a problem.

[scoobe]

yeah im hoping theres nothing related to it. the only thing i was suspicious of was a boost leak. I remember another member saying boost leak can be a very high pitch noise, but what im hearing sounds more like friction of some sort.


I am hitting full boost around 4000rpm though, i recentely took of my cars MBC and put on all the stock hoses and retrictor pill back in. i dont think i have a leak but what else could be slowing my boost progression?

[justin.jordan2]

I had this problem on my car. i found it was a boost leak coming from the back top of the intercooler. i just had to retorque the bolt back. it fix the problem. but i only heard it when i built one pound of boost and above.!!! so if ur still hearing it a negative boost i have no idea.

[SeattleJeremy]

If it's a boost leak your turbo will have a hard time reaching peek boost.
What is the peak boost? Does it hold from 4000 to 6000 (it's suppose to taper off after 6000)

[SD_GR]

The alternator makes a high pitched whine sometimes. No cure but also no problem.

[infox]

The alternator makes a high pitched whine sometimes. No cure but also no problem.

yeah, sort of like the noise a tv makes or when a computer monitor is going out right?

[SD_GR]

Yes that's a very good description of the noise. Mine's done it for years without any detectable fault in the alternator. I've heard from others that their cars do it too.