hi everyone its my first time posting here, but I'm having problems with my heater and i wanted to find the source of the problem, and i was looking around i noticed this red hose that I'm pretty sure is not supposed to be there its connected to the radiator and goes behind the engine and is connected to the other side of the engine i also noticed another hose that's not connected, but anyways can anyone give me some type of clue to what it could be?


hose that connects to heater core is behind this red hose

 

I'll check mine today and see what it's supposed to be connected to. I'm also having a no-heat issue right now.

Z1 motorsports sells a heater hose kit and it looks like the hose you found is NOT connected to the core, as it should be. See how it's ran here in these photos!
https://www.z1motorsports.com/z1-pro...et-p-3446.html

Here is what the heater core outlets look like: https://s3.amazonaws.com/img.partsbeast.com/yards/2/parts/293651/large/293651_8492e76b-3be4-44b1-be30-35c2cf79c66b.jpg?width=424

This is the outlet from the heater core hose. It should be hot when the car is at operating temp, slightly cooler than the inlet hose (yours is reddish).
https://www.z1motorsports.com/exhaust-tube-and-muffler/nissan/oem-vq35-rear-coolant-bleeder-port-p-7634.html