I have a '94 GXE and I have already searched threads looking for the answer to my problem with no real success. Here goes. When I turn on the heater, after letting the temp. reach normal I get maybe luke warm air out of the defrost and floor. As I get this semi-warm air the dash vents blow ice cold air. When I turn the control to vent- the vents blow warm air. Too wierd. I've replaced the thermostat, but I read were you cold clean the heater core and possibly solve the lack of warm or even hot air, but what about the cold air blowing out the vents while in the defrost/floor mode. I have a climate control type system. Like I said I've searched the threads but thought you guys might help. Any help would greatly be appreciated. Truemax

 

I have the problem with luke warm air also. When I switch to floor only, the air actually blows from the floor and the defroster. It never goes to full floor.

Your cold air through the vents problem sounds like fresh air switch is slid into the up position. I'm sure you know about that so maybe it isn't changing the damper to closed?

RickC

 

I too have a '90 SE with the electronic climate control (Canada), and mine does the same wacky sh&t. When I test drove the car, the heater worked fine. 1 day after owning it, the climate control wouldn't turn on at all - so I removed the circuit board and started fixing solders that 'looked' bad. I have defrost now (pitiful tho), but all the other settings blow out the wrong vents / or some are cold while others are luke warm / or all are ICE cold. I think it's the ECC circuit board. And the real b*tch of it is....., there's no schematic for that thing! Also, Nissan wants $840 (Canadian...) for the ECC!

 

make sure the lever on the left is pointing down. if it is pointing up it will let fresh air into the car and if it is cold outside lets that cold air in.

 

Thanks, That is definitely where the cold air was coming from. Daa! I guess I left it on from these warmer days that we've been having over the past few months. I have been reading other threads about problems that people are having with heaters and I think I'll try cleaning the heater core. Anybody out there done this job on there on. If so, could you tell me how you did it. I like to try it before I invest money in a new heater core. I know--heater core-- it can be big bucks.
Truemax

 

heat has been dying slowly and replaced a new nissan 82 C thermostat.
then got a really good radiator and put that in
cleaned the system........ then did a flush too..
I have less heat than before
it seems lower hose never heats up like top hose
will look into heater core today and vent doors too.
engine is hot runs half on the gauge.
I think system could be air bound?
the vent on therm is placed up as it shows,,,,, and the thermostat can only go in one way... the spring away from the block....
any one have a good idea where too look let Me know thanks !
Dave
running 50 % dilution on AF...and rad is 1/2 inch less than full.

 

[QUOTE]Originally posted by Bad_Daddy

I think system could be air bound?


Sounds like u need to bleed the sys. so your thermostat will open.