The neighbors are grilling again!

We live in a duplex house with an apartment at the back.  We share one walkway which goes to their residence that includes the back yard and basement and then my backporch and back door.

Walk into my backdoor and there is the kitchen.  I have two windows with one housing a window fan.  The neighbors start their grill up and the smell permeates throughout the house.  I cannot stand that scent and most times it makes me feel sick.

This goes on for hours before you even smell food.  They drink a lot, morning, noon and night, so maybe the grill is sitting there idle for a long time?

All I know is that I cannot tolerate the smell of the setting the grill up and then the fish they cook on it and then the ending smell.  How does one go about getting that scent out of the house.

I spray air freshener into the fan, put it on exhaust and nothing.  I cannot use a candle due to my younger son is severely autistic and a jar of smelley stuff - what in carnation is the name of the stuff that they sell in stores that smells nice? So that I could not use either.

Any ideas?  I hope the grilling will stop by the end of this month,but then again this is Los Angeles and people grill year round here.  I forgot to mention the smoking scent comes in as well from all their visitors who do it as they walk along the walkway and it comes in through all the open windows.