Cineburk, I was in the exact same boat 2 years ago that you are in right now. I bought a 98 Sienna that smoked on start up and at acceleration. I got turned on to this board (in the old format) and that is when I discovered AutoRX. Frank is extremely good to work (inventor of the product) and I was his first Toyota Sienna customer
! He worked a long time with me on how we should clean the engine.
However, in the midst of our cleaning application, which by the way was doing a great job as I took lots of pictures of my valvetrain and cut open several filters, Toyota made a "Special Policy Adjustment (SPA) for owners of these types of vehicles with the V-6 engine. This SPA extends the warranty out to 8 years and unlimited mileage on these engines as long as you can prove that you changed the oil at least once in the last year. Seeing as though you just bought it, you can go and get an oil change and there is your proof!
The long and short of it - Toyota put a brand engine in my van at no charge to me! Well, I did have to foot the bill for a new timing belt
...
While I whole heartedly believe in Frank's product and I continue to use 3 oz. maintenence dosages on both my 1994 Honda Accord and my Sienna, I could not turn down the offer for a free engine! I do not think Frank was offended by my actions as I continue to use his product and tell people about it all of the time.
If I were you, I would contact Toyota USA and have the VIN information of the van placed in your name from the previous owner - they will not give you any information about the old owner to whom it was registerd, I tried that already - and then file a claim under the SPA I described above. When you get through the process of getting a rebuilt engine or a new engine, it is at that point that I would start using AutoRX in the 3 oz. maintenence dosage.
BTW, I usually use Chevron Supreme 10-30 with the SuperTech oil filter and a 3 oz. AutoRx dose. Just so that I do not get stuck with a misquito killing machine again
, I change the oil every 3,000 miles. It's very easy for me to do and the weather doesn't get bone cold down here to where I can't perform the oil change!
Let us know how you proceed. You can't go wrong with AutoRX but if Toyota wants to help you out, that is all the more better...