No Heat at idle or while driving... PLEASE HELP!

[smj999smj]

If you still have poor heat, I would consider replacing the thermostat (genuine Nissan) and checking the heater pump. The heater pump is an electric water pump that sits inline with the heater hose on the left side of the engine and helps push the coolant through the heater core. It's mounted on a bracket that attaches to the firewall between the engine and the brake booster. It's sorta round, black plastic and has two wires going to it.

I just replaced the thermostat with a genuine Nissan t-stat. As far as the heater pump, I was under the impression only pathfinders with rear heat had the pump...? Either way I will check that tonight.

Yes, you are correct. The heater pump was only used on Pathfinders with rear heat. If you don't have rear heat, then don't worry about it. The heater pump is not available anymore unless you buy the $200+ heater pipe assembly. If it didn't come with it, I wouldn't install it.