The following problem I had with my buddy who is also workshop master a Mazda engine completely revised i.e. camshaft new 8 new valves on two cylinders cylinder head seal had cylinder head plan. Agr valve replaced and the high pressure pump as well as new sensors. Timing belts as well as wapu were also changed. Now I noticed after a longer drive that my coolant is completely full in the balance tank and also what was pushed out. Coolant is le Is dark discolored and I have so glitter particles inside where I find no explanation to myself. Ebend at the short start the wapu made strange sounds of this glitter ? I think that this stuff has killed the wapu and thus the head seal has gone ups and I then got back pressure. Vllt can explain to me what this is or someone has experienced similar things