Loss of top end power

You also might have an injector fouling.

Do this, and trust me, it might clear it up as well.

Go get a bottle of Redline SI-1 Complete Fuel System Cleaner and dump it in before you fill up the next time. It will clean you injectors up perfectly in one dose. It is recommended by GM, BMW, Toyota and is certified for use. Will not foul plugs or anything.

I am using it now and what a difference.

Here is a white paper on it:

http://www.redlineoil.com/whitePaper/15.pdf

Use the whole bottle for the first treatment, and then 3 oz per 20 gallons after that.

Will have to give Redline a shot. I was either dumping Techtron or Seafoam, sometimes Marvel Mystery Oil.