Like I mentioned in my previous post on of the coolant tubes was leaking. The tube was in bad condition, but the union too that went into the T joint pipe. Needed to take of the intake manifolds to be able to remove the T joint pipe. Replaced the union (part 106241) with a new one after drilling it out and re-thread it. This union is often leaking because of the corrosion. The costs of this little piece of aluminum.. a staggering 170 euro.