I am the proud owner of an 04 xj8. I have a coolant leak somewhere near the firewall on the passenger side. I have replaced the thermostat housing thinking that was the problem. I just can’t seem to find where it’s coming from. It looks like maybe it’s coming from a line that is covered in mesh and then it’s copper where it connects on the bottom. Does anyone have any feedback for me or maybe a diagram that I can actually see. Please help. I live in Austin, Texas and I have to work F1 tomorrow at COTA but I can’t drive my beautiful xj8 with this coolant leak

 

You might have to open up again... behind the thermostat is the valley hose . That just goes around and connects to the throttlebody (lover right side) . Put the car uphill or raise the front. To let it drain backwards so your knock sensors are not getting flooded ( corrosion damaged).
fluid coolant is Oat or G12+ silica free

 

Paasenger side near firewall can also be at the entry and exit towards the heatercore in the middle console behind radio.

 

Aren't they metal block style lines bolted into the firewall?