Hi everyone... I'm new to Infinity and new to this board. I have a 2003 G35 and I seem to have a heater issue... it blows cold air at idle. When driving the heater blows nice and hot. The rad is full of coolant and the reservoir shows coolant at the Max level... any ideas as to why it blows cold air when idling... like when stopped at a red light?
thanks so much......
Dan

 

Just based stricktly off past experience, this is normally caused by air in the system, or plugged heater core/hoses

 

You have air in your system. Look into bleeding it after you find the leak (if there is one). When the car is warmed up, the upper radiator hose near the reservoir should be solid and not collapsed.

 

thanks for the replies..... I'll look into bleeding it...

 

1. Check for coolant leaks, if found, repair
2. Remove radiator cap and warm up to temperature, make sure overflow reservoir stays at the correct level. The air should purge out by itself with the cap removed.
3. Check for 'flow' in the reservoir with a flashlight down the cap spout when the engine gets hot, you DO want flow, but not excessive bubbling.
4. Inspect/test rad cap. You can bring it into any local shop they should be able to test it quite easy/quick on the cheap. You only have to bring the rad cap in unless you supsect a leak in the system.

 

excellent... thanks again!

 

This problem happenned to me when i first got my g... I later found out that the top part of the radiator( The plastic section) had a leak... Just take it to a radiator shop and have them check for leaks..

The plastic + labor was $120 for me...My heater has been working fine since then. Don't let any repair shop fool you to thinking its the heater core because that will cost a lot of money

 

good advice...... thanks Darlll

 

The bottom of my radiator has leaked before. Right where the metal is crimped onto the plastic.

 

Enter Sir PW