Leak causing heath problems

My wife and I both drive and for the past 2 weeks we have both had a dry sore throat. At first we thought we were just sick but then we noticed when we got out of the truck for a day or so and then got back in the truck it would start again within one to three hours..

The only solution we have come up with so far is to keep our AC/Heater off in the front and back and keep all the windows open. If we do that we start to feel better after about 6 hours. I'm don't think it is an exhaust leak but I'm no mechanic. There is only a slight smell that I just barely noticed today that almost smells metallic and/or plastic or chemically.

I am putting my truck in the shop wail I have time off from the 4th to the 8th of July and need to know what to tell the mechanic's. If any one has any ideas or knows what the problem is I would be forever grateful for your help.

One final note. If we have the windows down and turn the AC/Heater on we start to get sick again.

Edit: Forgot to tell you my truck info. 2014 or 2015 not sure, manufactured on 07/14. Cascadia.

 

Good idea.

Another note. I was just walking around at the pickup location I'm at and could still smell the metallic and/or plastic or chemically smell so I'm guessing its not my truck that I'm smelling seeing that I only just noticed the smell today.

 

Just remembered more.
About 3 days ago I was driving and got really lightheaded to the point that I had to pullover for over an hour and walk around to recover and I felt like I couldn't catch my breath.

 

I'll have to
All I can see is the tops of them and they look wet thought the battery box cover is inside is not wet.

I'll check that next chance I get.

I bought a carbon monoxide alarm and so far it says 0 CO.

 

I'm in luck then because I got one with a memory.

Not even sure what that is. I'm guessing its the two black vents on the back of the cab about 1/3 the way up?