chris_h — The volume of air in the resonator chamber acts like a spring, which resonates against the mass of air in the attachment pipe, similarly to the way a mass-on-a-spring resonates. The resonance frequencies of the resonators are presumably set so as to prevent the intake-manifold noise (caused by "blowback" from the delayed closing of the intake valves in the Atkinson/Miller-cycle engine) from making its way out to our ears. Page EG-22 also mentions choosing one of the resonance frequencies so as to increase engine torque in the mid-speed range.

mda1224 — The "New Car Features (Functions?) Manual" was made available in this forum in November 2006 (by I think schmidtj). It really is a very interesting and instructive document. Since I don't have its location handy, I have just tried unsuccessfully to attach it to this post. The file size is ~6.4 Mbytes, which should be acceptable, since the "Manage Attachments" information specifies PDF files up to 10 Mbytes. I can send the file to you if you PM me with a suitable mailbox address. More usefully, can anyone figure out how to upload this file to this thread?

Stan

 

The attachments function seems to have different limits for different file types. Although it says 10MB for PDF, maybe it's not correct or really set that way. Try putting the PDF into a ZIP file and see if it likes that better?

 

Droid13 — I tried uploading a ZIPped version of the file (somewhat smaller now at ~4.9 Mbytes), but it also failed. I have found the same behavior in the past; if a PDF or ZIP file size exceeds about 3 Mbytes, it won't upload. This is very frustrating!

Stan

 

Stan,

Thanks for the information.

Chris

 

For US$10 per day, one can apparently access and download the Toyota "New Car Features" Guides, Repair Manual, TSBs, and other technical materials from the Toyota Technical Information System (TIS) Web site:
https://techinfo.toyota.com/techInfoPortal/
For only $10 one could download everything one wanted. This might be worth a try.

Stan

 

I've found it! It was made available by nash. His post #34 in the thread "List of pertinent TSB's" is here:
https://www.greenhybrid.com/discuss/...93/#post100867
and links to the PDF file of the "2007 Camry Hybrid New Car Features Guide." By the way, you'll find many TSBs of interest plus other technical information in the "List of pertinent TSB's" thread.

Stan

 

I also heard the same type of roar lately after a hard acceleration to merge into lane or passing. It sound like a truck with loud muffler driving next to you.

It will take about 30-60 sec before it will go away. Looks like the control value is not closing properly or immediately after full throttle.

Is this going to be a concern that the valve will fail to close eventually?

Anyone has similar experience?

 

I also had a wheel bearing go on our 09 14,000KM's. Rear right was making that whurring sound. Replaced under warranty