2002 Toyota Sienna • 202,000 miles

My van recenty started losing power when I press on the accelerator. When driving, the speedometer will drop down to 0 then a few seconds later jump up to 50, then fall back down to 0. It is like the van is confused and doesn't know if it is going or not. After losing power, it will all of a sudden accelerate back up to the speed I was going. The ABS light, flat tire light, check engine ight, and brake light are all on. Only the left half of the dash lights are lit. Have already taken in 1 time to be checked. They unplugged and cleaned everything. It helped for a couple of days. This is the second time to take into the shop.
January 3, 2013.

Get the trouble codes pulled so you can see what comes up for yourself. Any Advance Auto or Auto Zone will do this for free.