The Nissan Path

We bought my wife’s 2006 SE in July. When we test drove it, it was 98 degrees out and the a/c wasn’t working ( thought did not cross my mind to test the heat).

Last week, I got under the dash and had my wife switch the blend door from hot to cold and back again repeatedly. I could hear the actuator working. So I went under the hood and found the inlet and outlet for the heater core. Both hoses were warm/hot while idling in the driveway in 90 degree weather.

My driveway is a slight hill upwards, so I pulled the cap, while cold, and the coolant was right up to the top.

What gets me is the hoses to the heater core being warm/hot and still blowing cold air???

Thoughts???

has the coolant been drained and filled lately?

I just did my 2006 and replaced hoses and thermostat. Took awhile to burp out the air in the system, even while on ramps and incline. Not sure if this is any help to you or not, but wanted to throw it out there.

dawgn86 wrote:has the coolant been drained and filled lately?

I just did my 2006 and replaced hoses and thermostat. Took awhile to burp out the air in the system, even while on ramps and incline. Not sure if this is any help to you or not, but wanted to throw it out there.

I’m going to try putting it up on ramps this weekend and burping the system again. Maybe my driveway wasn’t steep enough.

The thing that gets me is the hoses getting warm or even hot going in and coming out of the heater core...

SMJ has a great write up on draining and refilling the coolant and gives good details on the "burping" of the air out.

UPDATE:

I set my PF up on ramps on my already inclined driveway. I followed the directions from SMJ's write up. Using my digital laser thermometer, and after holding 2500 RPM for 9 and a half minutes, I was getting 150 degrees out of the vents, then the truck died. Initial reaction was something went BOOM internally (feared the worst). I was able to back it off the ramps and onto a more level surface, and after a few seconds of cranking, it started up. Figured I was all set. The next day, very little heat with back roads driving, and the truck stalled out on my wife. Turns out I burned out the fuel pump (original) as she had less than a quarter tank of gas in her when I was running it inclined.

After replacing the fuel pump, the heat is still nowhere near what it should be. Last night I discovered both the overflow tank and radiator had 16lb pressure relief caps. I ordered the spring-less cap for the radiator as well and will try again after installing the correct cap.

I've also seen a few people using the spill-less coolant funnels and burping the system through the radiator. Should this be something to consider?

When I did mine, it took awhile and then I did more burping a few days later when engine was cool and both caps off. I also replaced hoses and thermostat.

Not sure on the caps, but if I got new ones, I would get the original Nissan OEM ones.

Good luck

Just an FYI, only 1 cap should have a pressure spring on it, that would be the overflow tank. The one for the radiator should just be a cap with no spring.

Update:

Replaced thermostat this past weekend. Topped off the radiator and filled the reservoir. I squeezed the upper and lower hoses and manually burped out as much air as possible. I decided to try something different that I used to do in the shop when doing a coolant drain and fill (Mitsubishi's). I used a "no-spill" funnel with radiator cap adaptor. Filled the funnel about 25% of the way and had my wife start the truck (in the garage on level ground). I figured the result would be the coolant getting sucked in the fluid started working it's way through. But what ended up happening was the fluid level kept rising in the funnel until about 80% full, which at that point I plugged the funnel for fear of it spilling out. I left it plugged until the engine reached operating temperature (i'm guessing thermostat opened at this point) then pulled the stopper out of the funnel. I would guess it would again suck the coolant in. Nope. just maintained the level it was at.

Now, every day after my wife drives it for a while, I wait for it to cool down and top off the reservoir. There are no leaks (no visible puddles or burning smells either). But it still takes way too long to get warm air, nevermind hot air.

I am going to try the ramps again this weekend. Will post another update.

Wow what an adventure!

palmerwmd wrote:Wow what an adventure!

I've never had this much trouble with a cooling sytem

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 also notice weak heat espically when using front window defrost. I notice the right side does not get warm at all, the left a little more, but seems the front face vents do get warm.

Do you notice differences in left or right side

smj999smj wrote: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.

BullDozer wrote:I also notice weak heat espically when using front window defrost. I notice the right side does not get warm at all, the left a little more, but seems the front face vents do get warm.

Do you notice differences in left or right side

I haven't noticed much difference in temp between the sides. To be honest, I've only checked what was within reach from the drivers seat

There is definitely no auxiliary water pump. Is it possible to add one?