One problem related to engine knocking noise has been reported for the 2008 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Toyota Sienna based on all problems reported for the 2008 Sienna.
While driving my vehicle it began to make a strange knocking sound as I accelerated. I had been driving around town for several hours that morning. I pulled over to inspect the engine, and saw some type of fluid on the left side of the engine and wall. I pulled the oil dipstick out and there was no oil on it at all. Completely dry! I had someone bring me some oil and I drove my car up to the repair shop just a short distance away. They discovered that the oil pressure line -valve cover variable timing-on top of motor to right on passenger side had burst. Part of the line is rubber and that part had ruptured and all the oil had blown out of the engine. My oil light did not come on at any time nor did my check engine light. Even after I stopped it did not come on.