Carbon monoxide is getting into car from the heater system as best I can determine.  I had Subaru dealer check and they can't figure it out..plus I had a local mechanic look at car.  Both checked exhaust system for leaks..none.  There are no codes showing.  With the air circulation on or the air conditioner it seems OK.  I was feeling sick when in the car so I put a carbon monoxide detector on front seat with heater blower on and  the alarm went off.  Anyone have any ideas??

Some kind of leaking fluid is getting onto the exhaust.

 

Could be oil leak, Power steering, or CV boot grease.

 

The fluids burn on hot exhaust, and then the smoke is pulled into the car.  (vent system draws air from the cowl area just behind the hood)

If a CO alarm is going off, I'm going to assume that must be an exhaust leak. Check the entiore exhaust carefully.

It could be a PCV hose leaking. I vented mine to atmosphere in another car and the heater would pull the fumes into the car. Not enough to get sick from, but enough I could smell it. The odd thing is I've had older cars with V8's that vented to atmosphere and yet the fumes never entered.

 

I'd insist the mechanics look it over again. If it WAS exhaust, you'd have a noisy leak + plus you'd probably be dead by now. Also, don't drive it if it's enough to get "sick" from and by all means, roll the window down if you must move it.

Edited October 29, 201411 yr by Bushwick