this just LITERALLY HAPPENED to me this week.......... its the O2 sensor..... and a slipping belt.

 

the o2 sencer and the belt?
or could it just be one?
im glad to hear im not the only one this has happend too.

 

this is weard im takeing to to shop in one week thats as soon as i can get it in as every one is away for sema
so i will let u guys know what the problem is.

 

i still havent found the problem but will let u know when i do.

 

could be the AUX fuel pump. 4700 RPM is about where the FMU will completely route fuel through the AUX pump. So if you are at full load and boosting at that RPM and the AUX fuel pump doesn't turn on you will loose fuel pressure go way lean and loose power or even have the engine cut due to lack of fuel.

Just a thought...

 

could be that too.