I’ve just upgraded my Mk5 gti intercooler to an S3 intercooler. I completed the job filled up the coolant and ran the car with the heating on full blast as per a video I watched (maybe I had the air con maxed)
The car ran for 5 minutes and then there was a big pop and a pressure release from under the bonnet.
I shut the car down, it looks like the air con pressure switch has blown off (the plug is broken now).
Any ideas what I’ve done wrong to cause this?
