Silly question how do you know if your intercooler is buggered ??
Having removed mine thanks to the turbo going pop, i noticed the fins think thats what they are called look corroded
I have looked on flea bay etc but most available are for a 300tdi
If the out side fins are cloged up you can just steam/wash the fins out
When a turbo goes tits up it can dump a load of oil in the inter cooler
If the turbo has broken up there will be bits of metal in the inter cooler
A local radiator recon firm can properly wash out and check your intercooler if its bad or you
If you wash the inside out your self you have to make sure all the water is out