If it is happening when warm, chances are it's a VCT problem not a manifold problem as they tend to reduce in noise when warm. Here's a nice 2553 post thread on what he is in for:PhasersEnjoy!
We towed our hybrid trailer, an 18 ft bantam flyer, for many years and many kms through the Rockies with our 2005 Sienna. Added airbags for stability and to remove sag. The sienna, as per the owners manual, had a 350lb tongue weight limit without a...
Check the switch for the brake lights. It may by damaged or misaligned. Even if your brake lights are working correctly, there may be a second switch for the cruise that is stuck or being triggered all the time making the cruise react like you are ...