If you weren't so positive about the accuracy of your CO detector I'd say it was carbon monoxide. Just a thought have you checked the detector to ensure it's working properly? Place it by the exhaust while the vehicle is running - it should go nuts...at least that way you know your readings inside the car are right.

If it's an allergy issue then sitting in the car without the engine running should have the same affect.

 

I would bet that the shift boot on the transmission tunnel is torn! What is coming in is a combination of burning oil and blow by. Pull the shift boot off of the console and take a look underneath it, there is another boot that seals the cabin from the exterior. Cheap fix for what ails you.

 

Even though you don't smell anything, maybe it has something to do with your heater core. It's possible something you're allergic to is in your core or cooling system. A long shot, but an idea for you.

 

check your headliner too.. the adhevsive in it or something used to make me a little headsick

 

Lots of good info guys-thanks to everyone-I'll be checking the shift boot today-the CO2 sensor does go nuts at the tailpipe-checked that before i even used it-car is having headliner redone so its not even in there. So we'll see-thanks again to everyone so far.

 

Radio Flyer-you may be the man-boots torn to pieces-I always thought there was a bit of any oily smell to things here and there. I'll keep my fingers crossed. Thanks.

 

When I ripped the hatch weatherstripping off another car I had I had the same symptoms, and it clearly smelled faintly of exhaust. There was no other leak, except for between the hatch and the body.

Is your hatch closed tight with a good seal??

 

No more huffin' gold paint while you drive.

scbmx has a point, if you're cooking antifreeze near your heater core that could probably generate some noxious gases. Check your AC as well, maybe you have a leak from that system.

 

sounds like its in your ducts but I might take them out ,then fill them with gas and set fire to them. even if your wrong It would be fun

 

that's what I would suspect, if the exhaust system is solid then it's coming in from the back. SUVs have been known to do that. Check weatherstip and all towards the rear

 

Thanks to everyone who replied, both serious and not so serious-the winner in the who-is-poisoning-me contest is scbmx87-I did have an inner boot tear(replaced), rotted tail pipe(replaced along with cat/muffler/front pipe), AND moldy carpet(removed along with door panels)-having done all that it still made me sick. Run my fingers along vents, have a little taste-hey, its sweet! Take a long ride with vents in off position, defrosting windshield with my jacket sleeve, no sickness. FINALLY. I never thought I'd say this, but I can't wait to take the dash apart. Thanks to everyone for posting info.

 

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