I have a problem with my heater. When I turn the fan on, it blows cold air out of the vents right above the heater control. It does not matter whether it is on hot or cold and it does not matter whether it is on heat, bi-level, defrost, a/c, or vent. No air comes out of the defrost at any time. I once had a vacuum line come loose from the vacuum tank under the hood and that fixed it, but know it is not working again and all the lines are connected.
There are also vacuum lines and connectors under the dash which can easily break given the age of the car. Scary prospect, but you may want to start some dash disassembly.
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1992 Yamaha FZR 1000. 145 Hp, all stock..
I have a 74 260z as well and did myself a favor early and ditched the climate controls, vents only. I bought mine in socal and have only put a few miles on it in the last 4 years so if yours is a daily driver I guess be careful getting that dash out and bring a friend
I have a sentra 2004.. and my heater also only blows out cold air.. i thought it was the thermostat because the gage also was going all the way up to hot.. Well i changed the thermostat but there's still no heat.. What's the problem??
This should probably be moved to the b15 forum but since I own one I will try to use old school logic. If the thermostat has been changed, and is working properly, then either your heater core has something blocked or the head gasket (which happens from time to time) is beginning to go. I am no expert but there are only so many things that keep heat from working. Email me if you don't have any success. Good luck.
260z heater/defrost
Linear Mode
