I few weeks ago some had a thread about heater issues, and someone else posted a diagram of the water flow through the system - can anyone repost this diagram? My heater has been only putting out luke warm air and I've been trying to bleed out the system this afternoon. The valve on the firewall is working properly, and I also disconnected the lines and ran a garden hose through the heater core to make sure it wasn't clogged up or anything. Water pump is new, and I think I replaced the thermostat a few months back.
One thing I have noticed is that the lower radiator line doesn't seem to have much water in it. I just ran it for about 10 minutes with the heater full hot, full blast, and still no heat. The radiator fans kicked on after a few minutes, then I shut it down. The upper radiator hose is nice and warm, but the lower hose is still cold and seems empty.
What's going on with this thing?
I looked all through my FSM and couldn't find a good diagram of the water flow, etc. Can someone steer me in the right direction?
Thanks!

 

I have somewhat of the same problem, Except for my cars temperature is always set on HOT. And when the car is in idle it goes very cold sometimes. And there is always hot air coming in during the summer months from the vents. Is this because of a vent not closing? something is up here with that

 

Wiking's cardomain site may help you....

http://www.cardomain.com/ride/748507/8

 

thermostat?
check cables/doors adjustment under dash on heater box.

 

uh oh...is this going to be in english?

ima check it though.

 

i hate to jump onto this thread, but my car only gets me heat when im driving (not just sitting at a light) or have been driving for a while. coolant is overflowing from resevoir intermittently...can hear coolant flow around dash....

started at same time i upgraded whole exhaust to 3" mandrel bent.

only thing i can think of is that engine temp is cooler than usual because of new exhaust; therefore, heating system isnt working up to par because of sensors logic.

or does anyone have a better idea?

 

You have air pockets in the cooling system...Bleed your cooling system of the air pockets...

 

Here's something you may want to try...
While the car is running, take the lower heater hose off its firewall bracket, and push it down towards the bottom of the engine compartment. This allows the coolant in the lower hose to flow downhill, instead of uphill like when it's attached to the firewall. I did the bleeding procedures, and still was not getting heat until I did this. Must have had some air trapped right there.

 

Can Some One Please Help Me 2 Get My 92 Maxima 2 Start And Run Da Previous Owner Told Me It Need A Head Gasket Sum Struts And A Heat Core My Aunt Drove It From Orlando 2 Georgia And It Broke Down In Macon Before It Even Got 2 Me I Got It Towed 2 My House And On Monday Im Gon Get It Delivered 2 A Shop Where All I Gotta Do Is Pay For Parts And I Help Wit Da Labor Free Labor Da Speedometor Also Dont Work And Probably Some More Stuff Any Suggestions Please

 

I read somewhere that in order to bleed all air from the system you have to get the radiator higher up than the heater core (jack front of car) otherwise some air bubbles won't get out.

 

If the lower radiator hose is cold and the fans come on this means to me that coolant is not flowing out of the thermostat even when the engine is warm. I'd start there making sure you got the correct one and that it's not installed backwards ( the big spring goes in towards the block not the radiator side). That's where I'd start to look.
Make sure they didn't sell you the wrong one. When I got mine the parts place told me that their system called out a 180 degree thermostat, yet, since I'd checked the book I knew it was a 170 degree thermostat.

 

it helps and is the recommended procedure by the factory

 

my problem was caused by the water pump going bad. replaced with timing belt. everything is cherry now.