Carbon Monoxide Headquarters

CO & Motor Vehicles





CO Exposure in Motor Vehicles:

A gentleman in Ontario, Canada wrote the following note to me earlier this year. He entitled it, "Carbon Monoxide: The Unspoken Option in 2000 Model year and Newer General Motors Cars"

"I have a 2001 Pontiac Sunfire GT and found out something by chance. There was a water leak problem in the trunk, so I returned it to the dealer for warranty repairs. I had to bring it back several times, because no matter what was done, it still leaked. After the third visit to the dealership, they said that they had sealed up everything that could possibly cause a water leak. As I was driving home over some wet roads, I thought I would check the trunk. It was wet again. I followed the wetness in my trunk to see where it was coming from. When the carpet was pulled back, I found the source of the leak. Water was coming in through a black box about 4 inches high by 6 inches long, an "Air Pressure Relief Valve" (APRV) (SEE AT RIGHT). The next morning, I was speaking with a good friend and told him what was happening. We examined his car, a 1999 Pontiac Grand AM GT, to see if there was one of these units in his trunk. There was none. After talking about it, I put my home CO detector in the trunk to see if exhaust gases were coming through it. In less than 30 seconds my detector was in alarm mode (ie. audible sound being made). I then purchased new batteries, thinking that the old batteries were bad. Again, I put my CO detector in the trunk and again it went into alarm mode. I then went to the local fire department. They looked at the reading flashing on my detector and said get in contact with General Motors (GM). I phoned the office of Owner Relations at GM and told them what I had found. I was told "if you do not like the way your car is operating, have your lawyer contact our legal department", and they hung up on me." Now I have to drive the car with the window open no matter what the weather, so I can limit my exposure to CO. I think a warning label should be installed on all 2000 and newer GM cars stating that operation of a new GM car may put a person at risk of being exposed to high levels of CO." If you see dust, dirt, wetness on the inside of the APRV, then your unit may be leaking too.

This gentleman claims to have made over 100,000 measurements of CO in his and other cars with two professional quality CO monitors, and says he has measured CO concentrations as high as 875 ppm in the trunk and as high as 54 ppm in the passenger compartment.


His message raises a number of important questions about GM cars fitted with an "Air Pressure Relief Valve:

  • Do sigificant amounts of CO enter such cars through these supposed one-way valves?
  • Are people using such cars in danger of injury or of death from CO entering the cars?
  • What will GM do to prove that the CO risk is nil through the APRV?

    Right: close-up photo of APRV in a late model Pontiac Grand AM

    The Webmaster welcomes comments from viewers. Send E-mail to "dpenney@cmb.biosci.wayne.edu".

  • Does your automobile have a APRV?
  • Have you ever noticed (ie. measured/detected) elevated levels of CO in your automobile?
  • Do you believe you have been exposed to CO in such an automobile, ie. ever suffered CO poisoning in a motor vehicle as the result of having such a device?


    CO in Automobile Exhaust

    CO in Automobiles

    Deaths from CO in Motor Vehicles

    in the Press

    ...... last changed 02/15/03



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