Okay....so I take my car to the dealership today and had them check out two things:
1) The "knocking noise" from cargo
2) The sulfur smell when accelerating (which i dont care what anybody says, should not appear even if using shitty gas).
Here is what happened:
The service manager came with me to replicate the problem. The first few minutes....not a peep came out. I mean the car sounded like a you were sitting in a Lexus LS430. Then, "DTUCK!" Yup, we both heard it, and again, and again, and again. What was funny was it happened whenever the car felt like making it happen. We tried hitting potholes, taking sharp turns, etc... it only happened once in a while, but we had an idea when the sound would be coming upon certain uphill driveway climbs, sudden turns, etc... Well, when we returned to the dealership, they put the car on a lift, and looked underneath. The mechanic found something unusual. The muffler seemed to have a fresh "bare" metal scrap, almost as if it was rubbing on another metal. So, he called me over, and had me sit in the car while lifted (this was a drive up lift, so it was safe). He began moving the muffler and making it hit where metal was scrapping it. He asked if the noise was the same...and, it kinda sounded like it, but not really. So, we checked everything; spare tire, rubber stoppers, rear cargo cover, plastic panels, etc...and couldnt determine anything. The guys at the dealership got stumped on this one. So, the service manager said, "since i heard the noise, and we were able to replicate the problem....we know there is a problem...and we know it can be fixed!" So, the dealership told me to bring the car back on Tuesday to have it looked at overnight and to be driven while someone sits in the back to find out where the problem is exactly....plus, I get the same car as a free rental until they resolve my problem...GREAT SERVICE!
Now, the Sulfur smell, is a known issue...especially with 03'-04' T4R...and the service manager said, "cheap gas has nothing to due with it!" He said the reason for the Sulfur stink is due to some catalytic converters made in Japan, and some outsourced to Japan, and something about ECU logic programming, i dunno...it kinda made scense though. So, he said, if we get it to make the smell again, you'll get the latest revision of the U.S. emissions spec catalytic converter and assembly. Sweet!
Overall, Im gonna get to the bottom of this, and hopefully make this a sticky when resolved cuz I know alot of you are having the same freaken problems!...otherwise...:bash: