i took the throttle body off the other day to change out my TPS and IAT. I was VERy supprised to see there was mass oil inside the intake manifold. the entire block is covered in oil from a slow and small seal leak (no idea where) and there were some oil on the actual throttle body. Is this normal? My mechanic friend that helped me change the opti out said he has seen it before and not to worry about it. Is this ok? will it hurt anything? whats going to happen?

The oil gets pulled in through the rubber hose that runs from the passenger side valve cover to the side of the throttle body. The purpose of that line is to supply filtered/MAF measured air from a port in front of the TB blades, to the passenger side valve cover. From there, the air i pulled through the crankcase and the lifter valley by the vacuum from the PCV valve. That keeps harmful blowby vapors from condensing in the oil and contaminating it.

If you spend a lot of time at WOT , or if the PCV valve is plugged up, or if your engine is starting to experience heavy blowby on the piston rings, the pressure will build up in the crankcase, and force the air backwards through the valve cover, where it picks up oil drops, and up the hose into the TB = the oil you see in the TB and intake manifold.

If this is the first time you've pulled the TB in 50K miles or more, the oil deposits are probably "normal". If the TB and intake have been cleaned previously, it might indicate a problem. As a minimum, check the PCV valve to make sure it is in good condition.

this is probably the first time the TB was taken off in like 130k miles lol what is the best way to clean it?

You can buy "throttle body cleaner". Thats the best thing to use. Some people use "carb cleaner", but the TB blades are supposed to have some sort of anti-coking coating on them that is removed by carb cleaner.

so i just spray this stuff in there and it will just drain out?

Use some rags to soak up what you wash off

I have an AMW catch can in the PCV line to catch the oil thats pulled from the crankcase.

AMW site

There are other brands too but this is what I have.