maxima blowing cold air while idling

[burtinos]

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

[1hawaii50]

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.

[fflint_18]

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.

[DAlastDON]

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.

Originally Posted by 1hawaii50

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.

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.

[fflint_18]

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.

[po8pimp]

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

[cheeo]

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

[hey11101]

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

[DAlastDON]

same heating problem (air in lines)

[ubersl]

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.

[cheeo]

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.