Hello Everybody, this is like my second post on this forum. I usually search but this time I didn't found what I was looking for.
I´m in the process or restoring my headliner, my car is zenki American market GT-S hatchback. I removed the complete headliner to restore it. And since everything is removed and the sunroof is in full access I would like to replace the 4 drain lines, they seem to be common nylon about 3/8" diameter.
I can buy new hose at the hardware store but I dont have any idea how the hoses are routed and where they end up. I already looked into the manual and nothing specific is shown. Im pretty sure that after 30 years the lines have clogged at least a little so its a good idea to replace them.

I tried to pull one out but it seems stuck, in a 30 year old car everything is brittle so I dont want to pull to hard and brake something. So far I have noticed 4 lines, 2 rear that I can only assume en up at the bottom of the car after the door and the 2 front that I can only assume end up behing the wheel arch.

Any help is welcome, I could post a DIY with pictures afterwards.

I would start by sending some heavy fishing line (125lb mono should be good) down the lines to see if there is any blockage. If they go through smoothly, try pouring a small amount of water down each one to flush out any dirt. Miatas commonly get clogged drain tubes and this is what we do with those cars.

Weed whacker line might also work well, and be cheaper than a spool of really heavy fishing line.

I'd expect the drain tubes to be clipped or glued somewhere along their length to prevent rattles and if they run clear, I'd leave them be. Too much chance old nylon would break up if you tried to pull it out without full access, then you'd have to clean out the bits before you could run new tubes.