Greg Perez

I have a 2004 Maxima with 156K on it. I've hade it since 30K and has been awesome. I am also a Serice Manager at a Nissan dealership an have access to OEM parts and Master technicians but they are stumped.

I developed a no heat at idle condition. There are no codes and the engine runs flawlessly. Pressure testing has revealed no leaks. We have replaced the, radiator cap, heater core and water pump. We have bled the cooling system as described in a Nissan TSB. There is heat afterwords but as soon as it is driven I lose heat at idle. When this happens we can hear water rushing in the heater core area as if it is getting air bound somehow yet no leaks can be determined.

I bought my wife a 2006 and need to sell the 2004 but need ideas on possible causes of this problem. Any help would be appreciated.

maxprivate

iTrader: (12)

What about the thermostat? Check the service Manuel for testing that as well.

jasoneon

Mine did the same thing a year or two ago and my mom used to have an 05 that also did the exact same thing....even the water gushing noise if you revved it up a little. Both were a little low on coolant, I added some, fixed the problem in both cars. I've noticed that the heat isn't as hot at idle though but it's still pretty warm. With the stuff you've already tried, I'm stumped too.

Greg Perez

Well I finally resolved the problem. I was thinking back to maintenance I had done and this spring I had done a coolant flush. I was convinced that my issue was due to a flow problem but the boys wanted to do another flush. I figured it couldn't be that because it was just done. Yesterday we did a coolant flush with a heavy duty cleaner which also required driving it at full temperature for at least an hour. Well the amount of crap that came out of the radiator was incredible. We flushed out the system afterwords a few times and the problem is now resolved. Thanks everyone for your input and I hope documenting this experience might help someone in the future.