I had a little run with a poll while parking, denting the rightside of my car justbhind the bumper (1992 Volvo 740 turbo) well ever sense then my car makes this really really really high pitched noise when the turbo kicks in, and accelerates like crap. I replaced some hosing that looked to be in poor condition, but it hasn't helped. Any one know what exactly might be causing the sound? How to locate the sound? or have any other idea/tips?

It is probably the intercooler as you indicate in the name. The units on these have plastic sides which are held on by glue.

many things can make these split and leak, primarily up'ing the boost (i found that one out), but if you have had a knock and its shifted it a bit, you could have split the glue somewhere.

with the engine running, spray a load of water (with soap in it, like washing up liquid) on the hoses and sides of the intercooler so it is soaked, then just depress the throttle under the hood, and it will bubble wherever your leak is.

Matt