My 2013 LR2 is producing Excessive Cabin Air pollution. It smells like some burning engine fluid and is coming from the vents. The pollution becomes more excessive:
- Just after car startup
- During colder weather (and gets extremely worse in freezing temperature below)

The indoor/cabin air pollution is excessive and we also have to open the windows to let it out. I have also noticed a slow coolant leak but not sure if this is related. I am afraid that this may be harming our health. My cabin filters are up-to date. My local mechanic tried to diagnose the problem and changed the heater core but this did not fix the problem. Does anyone know what the problem might be?

 

Heater core would be suspect #1.

But the vent blower inlet is located in the shrouded area between the engine compartment and the right hand front seat area firewall... if you have something leaking, fumes might get sucked in when idling, although I suspect it's designed so engine airflow can't get in there while moving.

Can you tell the difference between coolant smell and oil? In addition to coolant, you have engine oil,power steering fluid, brake fluid, and transmission fluid under the hood. I have the older i6 engine, so can't help with specifics but if you clean the engine thoroughly and then drive it around you might be able to see a fresh fluid leak either from above or under the car (might have to remove the bottom splash guard). Clean it when it's warm but not hot, if water makes steam on the exhaust it's still too hot. Use a fine spray and avoid focusing on any air inlets. I just use water, but you can buy degreasing stuff in a can that you spray on and then rinse off.

 

Changing the heater core makes no sense. The climate control system has to get air from somewhere to heat or cool the cabin. The core should not have been changed unless actuating the air recirculation control had no effect on this, and even then that would not solve the root cause of the problem in the engine compartment. You will have to track down what is leaking/burning to resolve this. If you are not a mechanic I suggest you take it to a mechanic who is competent on land rover vehicles.

 

Undoubtedly this is detrimental to your health. Seek qualified assistance soonest.
Add to the suggestions, ensure that filter is an activated charcoal filter and not just a bounce sheet.