Ford investigators are near-certain they know what's causing the possible release of the poisonous gas into their Explorers -- which the Austin Police Department recently removed from their fleet due to officers becoming ill -- KVUE and Austin American-Statesman reporter Tony Plohetski discovered on Tuesday.

Ford officials have said from the start they believe the issue is a result of up-fitting done by departments and outside vendors, and in conference calls with reporters Tuesday the company went public with new evidence they claim supports that theory.

The company released photos exhibiting holes drilled into cars for various things such as strobe lights near the license plate and battery cables underneath the vehicles. Officials said improperly sealing those after modifications just like these could lead to carbon monoxide being released into the cars.


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Company officials said these preliminary findings are the result of investigations in Austin and at other police agencies across the country that have experienced the same or similar issues.

In some departments, officials said they have sealed those holes properly and that they have seen very positive results in subsequent carbon monoxide readings.

Austin officials have said previously that some of the modifications to the APD fleet were done both internally and by a Ford dealership outside the Austin-area. Meanwhile, Ford said in conference calls with reporters Tuesday that they will be working with Austin police to seal these holes in hopes of getting them back on the street as quickly as they can.

APD previously said that about 400 police interceptors were pulled from its fleet until it could resolve this issue.