Have no heat!

[zackje07]

In my wifes 2003 I35, she gets has no heat. It just blows out cold air. What may be the problem?

[2004MaxSE]

I have a similar issue with my Maxima. I'm not sure how to fix it but I get heat when accelerating, but not at idle. When cruising everything is fine, but when I get to a light or a stop sign I seem to get A/C instead of heat. I've never seen this in any car before and I worked in automotive for 15 years.Just to see if we have the same problem, try reving your car at around 2500rpm and see if you get heat. Obviously wait til the car warms up first.

[lightsout]

maxima's defroster works through the ac compressor and moisture reducer, check your compressor oil, and A/C Clutch.

i'll look into this more...but that's all i got for now fella's

[maxhopper]

Sounds to me like a blend door issue. If it's not closing, you will get ambient air coming through the vents. When you are driving and get warm air, it's probably coming in from the engine compartment.

[2004MaxSE]

Sounds to me like a blend door issue. If it's not closing, you will get ambient air coming through the vents. When you are driving and get warm air, it's probably coming in from the engine compartment.

If the temp outside is chilly enough that I need to warm up my car before I drive, I can start the car and put the heater on high expecting to return to a warm car but instead I get in to cold air blowing on my feet. The second I touch the accelerator even at a stand still in park, I get hot air (not just warm, but hot).I have a feeling it has something to do with the pressure at which coolant is travelling through the system. When I accelerate I get full pressure.

Anyone ever heard of these cars having two thermostats in the system? I was told they do and if the first one opens but the second doesn't, then that is when I get cold air.... I'm no mechanic, but that doesn't make sense to me because once the car is warmed up and I am getting hot air I shouldn't get cold air again until the car is shut off and cooled down. I can drive all day currently and have this issue ALL day. It's wierd

zackje07 did you get a chance to try my suggestion? I should have mine fixed by this weekend so if it's the same problem I have I can save you the diagnostic cost at least.

[xerexabante]

check you coolant level