Heater doesn't work at idle

[ncuster]

My heater only works when I'm driving. At idle, the heater won't pump out any warm air.

I haven't noticed any fluid leaks and the engine coolant is at the appropriate level. Any ideas here?

Thanks!

[SteveTheTech]

Have you had a coolant flush recently?

If so there are two things that you need to have addressed.

1-Nissan VQs need a 50% ethylene glychol to 50% distilled water to perform in ideal conditions. The only way to correctly test this is by using a refractometer to inspect EG/H2O ratio.

2-There very well may be air in the cooling circuit. The air gets in there when either a vacuum is not drawn on the cooling system before adding the new fluid, or it was not purged of air properly.