hello everyone, i have a 2004 nissan maxima sl. when the car is warmed up and the car is idling the heater will blow cool air, but when i am driving the car blows hot air like it supposed to. any input as to the problem is apreciated

 

My first guess would be a clogged heater core. I would do a really good flush on the cooling system using one of the chemical treatments from NAPA. I had this problem on my Taurus, and ended up replacing the heater core. Not sure whats involved in a heater core for the Max, but I had to pull the complete dash for the Taurus...lots of fun when you're working by yourself.

 

Or a soon to be bad water pump. At idle it's not moving enough water through the core to give you heat.

Give it a flush and pray.

Never did a 6th gen core, but my guess is it's a pain. I think I'd rather do the pump.

Good luck.

 

Make sure you coolant level is full.

You could have an air bubble and need to "burp" the cooling system.

A coolant flush never hurts. I Flush my vehicles every 2 years. It helps in preventing clogged heater cores and failing water pumps. Preventive maintenance goes a long way.


Dude, i feel your pain on the Taurus. This past weekend i changed the heater core in my brothers 1997 Taurus. I had no idea what i had gotten myself into until after i got started. Complete disassembly of the lower and middle dash including dropping the steering column to the floor. I have never taken a dash apart that much. It took me 9 hours to do the job by myself. He has had the car since 1998 and has almost 300k miles on it without a coolant flush. He is the worst when it comes to taking care of his car.

 

Every Taurus of that generation has has a heater core issue no matter the miles.

And because of the multiple thousands people want to chargee for what you did allot either sell the car or go without heat.

 

had same problem, it is air in you coolant lines. easy to fix. i will find instructions from an earlier thread

 

hey i have the same problem, could someone post how to fix the air in the coolant lines please

 

Same problem here also, if anyone knows how to fix this easily that would be a great help.

 

http://forums.maxima.org/6th-generat...air-lines.html

 

Twice I did coolant flush at the dealer and both times I got this problem. Had to go back so they could get rid of air in the system. There is a factory procedure (TSB) on doing it yourself. It takes about 1 hour.

 

just an update with mine. i tried to get the air out myself, but that didnt work so i brought it to the dealership and they said i had a bad rad cap that was letting air seep in.. they charged me something like $26 for the cap and bled the line and its working fine now.

 

Hello, I am new to the forum but got some great help yesterday so I wanted to respond. Had the issue of heater blowing cold in my 07 Maxima when idling but otherwise it worked fine. I parked on an uphill slope in the driveway and as advised removed the radiator cap and bled some air bubbles out of the radiator and filled the overflow bottle to the upper limit. I then drove the car and repeated the bleeding process and my heater now works perfectly! Thanks for the advise!