Here is an update.
I used fuel treatment kit by CRC called "CRC Industries Guaranteed To PassŪ - Emissions Test Formula".
It was used it according to directions, and I went in and erased my P0240 code.
Three days passed before the code reappeared; verified by the SES light on the dash.
My code reader came back on with a red light and the dreded P0240.
Anticipating this situation, I ordered another Bank 1 manifold assy. (at a great price) .
Knowing there was some time before the new manifold arrived, I decided to try one last product.
The product is made by Prestolite Performance and called "Cataclean" fuel and exhaust system cleaner.
Once again, I used the product according to directions while erasing the existing code in the process. Today was day 3 with no SES light, but figured it was just around the corner. I was going in for the emission test today, and figured I would plug in my code reader before I left the house just to see if I might have a yellow or red light.
IT WAS GREEN ! NO CODES TO REPORT!
I was floored...was it a combination of both treatments? was it just the Cataclean?
Just do not know for sure, but I do know this...I passed emissions with Flying Colors.
Well, now I have a fresh manifold to put away when it arrives....you know, it does not bother me one bit. I am not sure if my situation was an exception, but I strongly recommend these chemicals to anyone faced with the cost of a new manifold and the dreaded P0240. Two tanks of premium fuel and about $40.00 in treatments saved a lot of headache.