Update:

I was in a hurry when I made my first post.

My Runner has 150K on it. It is the 3.0 engine. 2 Years ago I did a Timing belt and all the front parts. I did not do a valve adjustment. Last summer I noticed that on a long trip I could hear a lot of valve noise. I also noticed a coolant leak in a hard to reach spot. I fixed the leak and I did not drive it over the winter. Last week I started it and took it into Toyota. The dealership did a valve adjustment and lube & Oil. When I picked it up it was running way better. On my way home that evening I decided to see If I got some power back. I accelerated as I was climbing a hill, only to have it buck and sputter. I had put fresh gas into it before on my way to the dealership. And I notice that when ever I slightly lug or power hard I get the stumbling and hesitation. New plugs, plug wires, cap, rotor Etc.

Any Ideas? TPS.... MAF???