The Washington State Patrol is equipping hundreds of its vehicles with carbon-monoxide detectors after six troopers since January have reported feeling sick from possibly inhaling exhaust fumes. Crews will install the devices in 634 Ford Explorer Police Interceptors over the next few weeks, according to State Patrol Capt. Shane Nelson. The move comes amid a months long federal investigation into a version of the Ford Explorer over worries of exhaust-fume problems nationwide. Ford has responded to the numerous carbon-monoxide claims by promising to make repairs as it investigates the complaints. According to a statement on the State Patrol’s blog, six troopers reported symptoms associated with possibly breathing in carbon monoxide while at work in Interceptors, a high-performance version of the Ford Explorer used by law enforcement. They made the reports January through mid-July. Two troopers were hospitalized, and released, Nelson said at a news conference Friday, which the State Patrol streamed online. Officials confirmed there was measurable carbon monoxide in the system of one of the troopers. Both have returned to work. “We wanted to get in front of it, make sure everybody was protected,” Nelson said of the detector being installed in troopers’ vehicles. Symptoms of carbon-monoxide poisoning include dizziness, weakness, shortness of breath and nausea or vomiting. Meanwhile, the National Highway Traffic Safety Administration is investigating complaints of exhaust odors and possible carbon-monoxide exposure in 1.33 million Ford Explorers across the nation. Among the complaints, three involved crashes and 41 were reports of injuries, such as loss of consciousness, nausea and headaches. In Texas, the Austin Police Department has pulled nearly 400 of its Ford Explorers off the street. More than 60 officers there have reported health problems since February, and more than 20 were found to have measurable carbon monoxide in their systems, city officials said. Ford said in a statement it has discovered holes and unsealed spaces in the back of some police-department Interceptors that had equipment installed after leaving Ford’s factory. The company said police and fire departments routinely drill holes in the backs of vehicles to add customized lighting, radios and other equipment.