Ugh.... I Need Some Help Identifying a Coolant Leak

[Steve Tinker]

When was the coolant tank last replaced?
On inspection, my old tank was bone dry and there was no evidence of leakage - until I unbolted it and felt (you couldn't see) encrusted coolant on the rear portion of the tank. When I physically removed the tank, there was 2 cracks which only leaked when it heated up - when cold it held the fluid and did not leak. It was enough to lose half a litre every 1000 km.
The other leakage(es) could be around the pump / thermostat / radiators (bumper removed), but that would mean getting the car on jackstands and exploring for visual evidence with a strong light source....
Your pressure test would (should) simplify the search.

[thom4782]

Thanks Steve -- the tank is original, hopefully that's the cause. There may also be a leak in the passenger side radiator. I hit a curb a month or so ago and it damaged the underside of the fender liner.