I have a 2003 sport trac,Its bogging/stalling out when I pass 3000 rpms.

Thanks my friend,Also the engine light is not on,I have 150000 miles and have had no issues,I drive a half an hour to work and back,and thats it,How would i check the catalytic converter?i see you have a Shop??

Well, there are special tools that you would use, the easiest being a scan tool. They do make what is known as an exhaust backpressure tester, it is basically an adapter that screws in in place of the oxygen sensor. The other end connects to a pressure gauge, when you run the engine at various RPM's, you note the pressure reading on the gauge. Problem is, this tool can be hard to install on some vehicles due to the location of the oxygen sensors, especially if you are doing it at home, and this may not be a case of exhaust restriction at all, we are still assuming that it is a cat restriction at this point based on your description. Honestly, your best bet is to take it into a shop you trust, tell them the symptoms you are experiencing, and let them take it from there. A good quality scan tool and a knowledgeable technician should be able to find the root cause of your issues fairly quickly and at a reasonable price. It may also help to drive it some more, if the MIL is not on, it may be because the ECM has not had enough time with the problem present to turn it on. Having the MIL on when you take it in for diagnosis typically helps quite a bit, so if you can drive it SAFELY for a few days, it wouldn't necessarily be the worst thing in the world. I don't think I would drive it for more than a few days or more than around 100 miles in it's present condition though, so as to avoid damaging any other components.