So while I was underneath the car replacing the coolant, I noticed a wet hose fitting attaching to a cooler in front of the radiator. Thankfully it doesn't seem like its a fast leak, but it bugs me nonetheless.

My power steering system has been quite hard to turn in the past. I replaced the fluid with Lucas stop leak, and that appeared to help. I have heard from a friend that the steering rack could have an internal leak. However I am confused what this leak I spotted is coming from (didn't think to check where the line went, was in a rush ).

Does the FC have a power steering fluid cooler? I have searched but could not turn up much. According to a diagram I found there does not appear to be one. I'm guessing its an engine oil cooler.

I have an 87 S4 sport. Thanks in advance.

 

There is an engine oil cooler up there as well as a "cooling line" for the power steering.

The fluid that's leaking should tell you which system is at fault.

 

Gotcha. I will have to open it up and take a closer look.

I see Mazdatrix has oil cooler lines, but I can't seem to find the power steering lines from anywhere that I am familiar with. Where are the power steering lines available?

 

If your oil cooler has ever had its lines removed, the crush washers should be replaced. They can be annealed with a common butane torch for reuse, but sometimes we all forget and it sprouts a leak.

Not sure if the power steering lines are available, but I'd imagine they have crush washers on the fittings as well.

A nifty trick to check for leaks in difficult spots is to use a Q-tip in a pair of needle-nose pliers and see what fluids come out. Oil is yellow/brown, Power Steering Fluid is Dexron II ATF (Red). The Q-tip trick is really handy for checking the tight bends in the heater hoses at the firewall.