2006 whistles

[mr_tw]

I have a 2006 Corolla LE with an automatic and136k.
The engine whistles under hard acceleration only. The whistle gets higher pitch as the rpm increases, but it only appears under heavy throttle, light throttle at high rpm produces no whistle, it's only audible with the window down, and the wind noise with the window down easily drowns it out above 80kph. I searched the forum and was unable to find anything related.
Any help is much appreciated!

[Brian R.]

See if there is a leak in the intake system. Check from the throttle body to the air cleaner. Those tubes and connections can crack. Also, they may be installed incorrectly and leak.

[mr_tw]

Another couple things I forgot to mention, I have replaced the intake manifold gasket, and the throttle body gasket. The other issue that may or may not be related is my fuel economy has dropped 7-8 mpg. But I don't check my millage regularly, so I'm not sure if they are related. Well go through and check the vacuum lines tomorrow. Are there any tips or tricks for checking them?

[somick]

Originally Posted by mr_tw

Another couple things I forgot to mention, I have replaced the intake manifold gasket, and the throttle body gasket. The other issue that may or may not be related is my fuel economy has dropped 7-8 mpg. But I don't check my millage regularly, so I'm not sure if they are related. Well go through and check the vacuum lines tomorrow. Are there any tips or tricks for checking them?

Spray questionable spots with water. The change in sound will indicate the problem.

Good luck,
Sam