Just got the old intercooler out, I can see some minor damage on that side on one of the cross members and that side of the intercooler is filled with muck. Guessing that side of the car has been off the road and clipped something putting a hole in the intercooler. Then all of the oily boost sprayed out that side picking up more muck. The intercooler was held in on one side with a 12mm bolt not really attached to anything, the other side has a 10mm bolt which promptly sheered off. I also saw that on the side with the 12mm bolt the plastic had been cut to probably cut off the original bolt. The other side of the intercooler is metal so I'm guessing they didn't bother trying to remove it. The intercooler is stuffed full of muck and rubbish with fin damage on the plastic side. I have a replacement intercooler coming which I will hopefully fit next weekend.