Air flow weak on passenger side.

What is the mode door? How long would take to replace them myself? $1000 dollars is a little steep for that I think. If it difficult to get to everything would just be worth it to replace everything that can be replaced to avoid having to take everything apart again?

If the airflow is weak on the passenger side only but the temp is the same as the driver then it’s probably the seals between the heater box and the dash. That foam That’s being used doesn’t hold up very well. The blend doors ONLY effect the TEMP

Ive got weak airflow but the heat and ac both work fine is that still the seal between the dash and heater box.