The car is a 2011 M37x. I just purchased a new cabin filter but I'm sure it's unrelated. The heat will only blow out of the driver's side vents (windshield defrost vent and face vents). Ambient air blows out of driver's side foot vent and all passenger side vents.

Any thoughts on troubleshooting? The car probably hasn't had a coolant drain/fill since it was born. I've only had the car for 2 months, so this is *new* to me. Not sure what it did prior to my purchase.

Car heats up to operating temp just fine and maintains operating temp just fine. Possible faulty thermostat? Clogged heater core? Thoughts?

 

Is it in dual mode? (Separate control of driver and passenger side?)

 

lol. no, it's not in dual mode. Both sides read 90F and passenger side blows out ambient air. Driver's side blows out only mildly warm air.

 

Bump. Any thoughts?

 

Warranty left? Take it to the dealer, grab some breakfast, and let them handle it.

 

No warranty left but it will be looked at by the dealership next week.

 

Oh- that sucks. Do you have a local mechanic who can check it out? My local guy takes care of me and won't nickel/dime me on stuff.

 

Completely forgot about this thread. Yeah, I do have a local. I was involved in a minor rear ending accident and had to get my front bumper changed out. It took about 2 weeks. The dealership told me that the heater core was bad, but before I go into tearing up my dash, I will take it to my local to see what they think. Heater core replacement was quoted at around $1600 labor and parts from the dealership. Car will be benched for the rest of winter so i won't revisit this until the spring at the earliest.

 

doesn't sound like a bad heater core to me since you stated heater is working on driver side. the last time i checked car's usually have one heater core unless you are driving a minivan or large suv where theres a secondary heater core in the rear of the car for heating operation for rear passengers. to me the fault in no heat on passenger side may be a stuck blend door actuator or possible a lever/rod for the actuator may have come off. are you sure when you replaced your in cabin filter you didn't accidently bump off a blend door lever or rod? i would start there first.

 

Good Luck...I had the 60k done on my M37 with a coolant change and shortly after that had what sounded like water in the fire wall. I took it back to the dealership and the bled the system for air. While doing that the tech noticed that the air on the passenger side was not warm as it should have been. They asked me about it but I never ride on the passenger side. So after two days of running test and trying to figure out what happened with the heater core they ordered a new one. Well it was on back order with no ETA so the ended up having to replace the complete assembly. So $3,100 later (thanks Infiniti Elite Warranty ) the problem was fixed. So i hope that you don't have the same issue I had but I must say that they took really good care not to damage my stone interior and silver ash wood trim...

 

I haven't actually replaced the cabin filter yet. It's just gotten warm this week but haven't had the time to do it. I also suspect that the heater core is not the problem but based on tech37's post it very well could be.

I've been lazy about it and will probably revisit it again in the fall when it starts to get cold again. At this point, there's nothing to keep me from driving it since it just started to get into the 40s and 50s. I'll bring it to my local first to see if they can properly diagnose it and repair it. I'd rather not DIY a heater core.