Normal O2 content is 2.94 psia, 2.2 is around where you'll black out. A car, due to the compression, should be able to deal with lower oxygen content and keep running. It will be running rich, which will start production of CO.

Now, how the O2 sensor and ECM will respond to reduced O2, I'm not sure. It should lean out the mixture, but how lean it can adjust will depend on the programming.

It's funny, in some movies, they still think that CO from cars in a garage will kill (Office Space). And some places, they still think sticking your head in the oven will kill you. We haven't used coal gas (H2 and CO) in heaters and ovens for nearly 100 years.

if you put your mouth on the pipe itself, it could kill you if the pressure was sufficient to explode your lungs and chest cavity, or scrunch down your cardiac output from the pressure. of course, your lips would have to be firmly held on the pipe.

The CO2 will get you first. Carbon dioxide is deadly if breathed for an extended period of time at a few percentage points of air -- even when you still have normal oxygen levels in the air. You could NOT, for example, replace nitrogen in the air (by anything much more than around 2%) with carbon dioxide and expect to survive breathing the carbon dioxide-rich air mixture.

I took my 911 in several days ago for it's very last emissions test.
The last time I did it, the guy running the test said that if I'd driven through a long tunnel, the air going out would be cleaner than the air going in.
This guy said that I could run the car for several hours in a closed garage without any problems, she runs that clean.

Cars today are amazingly clean running. That carbon monoxide from the old Rambler that would finish you right off.

CO2 would kill you - but you would be having a puke fest first - and time to think about it..

just run a few tanks of leaded fuel first, that oughta do the trick

If you tried it with a hydrogen fuel cell vehicle with only H2O coming out of the tailpipe, you'd likely just drown in your sealed garage... ;)

I'd think eventually the motor would still burn the oxygen... Or convert it to water as the case may be....

:eek:

There was a comment on the board, years ago, about someone coming back into the house after working on the car all day. The area around his mouth was black. His wife made some sort of comment like "Oh, you're giving the car Blow Jobs now?".