About 2 years ago, I wrote about a pronounced rattle/clatter/knocking sound coming from my engine at operating temp, at idle and low engine RPM's.
Two dealers said they hear the noise, but said it's normal.... Well, it seems there may be a fix from Toyota. I saw at the Jasper engine site, a Bulletin released about a redesigned intake manifold that is a cure for the problem. Here is the bulletin dated 11/04.
"Engine Noise On 2002-2004 Toyota 2.4L
2AZ-FE Engines""AERA members have reported an engine noise on 2002-2004 2.4L 2AZ-FE engines. This noise has been described to resemble a rattle or spark-knock type sound and is most prominent during light acceleration. The noise may also be heard during idle conditions, while the engine is at operating temperature. It has been determined that this condition is created by air movement through the intake manifold.
To resolve this type of customer concern, Toyota has developed a revised intake manifold for the affected vehicles. This manifold is available from Toyota with Part #171200H010. The revised intake manifold has been installed into year model 2004 vehicles beginning with the following engine codes: 4T1BE3#K#4U262489 and
4T1BE3#K#4U790816.During installation of the revised intake manifold, make sure to install a new gasket and torque the five bolts and two nuts to 22 ft/lbs (30Nm). Information is from best available sources and is accurate at the time of publication. However, Jasper Engines & Transmissions ASSUMES NO RESPONSIBILITY and cannot be held liable for any results or consequences regarding the use of this information."
Well, time to get my documents in order, and have a visit to the dealership to finally rid my car of this terrible problem.