OK, I'm about to give up! I have a 99 Ram 1500 with the 3.9 V6. It has a intermittent idle problem and eventually gives me a code that says "O2 sensor voltage to high(bank 1 sensor 1). I pull up to a stop light and the truck tries to die. I can hear air rushing into the engine. I've changed both O2 sensors, IAC valve, map sensor, cat convertor. I've removed the throttle body and use a whole can of throttle body cleaner on the passages, reinstalled it with a new gasket. After resetting the computer, it will be fine for about 30 minutes, then it starts all over again. If I ignore the check engine light for about a week, it runs ok but only get about 10-13 mpg. Question is what causes this particular code and could it be causing my idle problem? Where do I turn next? Any help would be greatly appreciated!

 

If you hear air rushing, you probably have a vacuum leak somewhere.

A vacuum leak will cause a rough idle.