' 06 V8 won't rev

I have a 2006 V8 that won't rev past 1800rpm. Starts and idles fine. In the beginning was losing power intermittently. Then wouldn't go above 60mph. Now it won't rev past 1800 rpm and problem is constant. Starts easy and runs smooth. Revs to 1800 rpm then falls on its face. No codes stored or check engine light. Any ideas?

 

With no codes...typical suspects:

Bad Cat. A semi-plugged cat will idle fine...but will bog under acceleration.

Weak Fuel pump. Again, idles fine but no fuel when accelerating.

 

Also, if not done already, check all vacuum hoses and make sure the tubing for the air intake is in good shape.

 

First thung I checked was fuel pressure. It's well within specs. The way this problem started intermittently and becoming more frequent over a period of months before becoming constant virtually eliminates the cat as the problem.

 

The first thing I checked was the fuel pump. Pressure is well within specs at all times. The way this problem started intermittently becoming more frequent over a period of months and finally becoming constant virtually elimates the cat as the source. I suspect the drive by wire throttle body.