DENVER -- Volvo and the federal government has issued a massive recall following a 7NEWS investigation that occurred more than a year ago.

The recall from Volvo and the National Highway Traffic Safety Administration may affect 170,000 cars in the United States. The total number is closer to 360,000 cars; however, many have already undergone the temporary fix.

Don Willson, a longtime Volvo owner and retired engineer, spent years researching a problem with Volvos and what he found, he showed to the carmaker, to NHTSA and to 7NEWS Investigators.

Willson discovered an apparent design flaw that could leave drivers without complete control over speed and power.

"This is the electronic throttle module. It has a part in it that will fail. The car can surge, it can hesitate," said Willson. "It is scary."

Through internal documents, 7NEWS discovered that Volvo knew the part was failing, at an alarming rate, long before the cars ever hit the showroom floor.

In the recall notice NHTSA references a "throttle control malfunction" and is requiring Volvo to upgrade software in the cars pertaining to the system.

Willson believes the recall falls short.

"It is a recall. It does admit there is a problem, but it has not fixed the underlying problem of this little part wearing out," Willson said.

On Wednesday afternoon Volvo issued a statement to 7NEWS saying, in part, "Volvo does not believe the condition presents an unreasonable risk to safety. However, to avoid protracted discussion with NHTSA, Volvo has decided to take this action."

The recall affects Volvos from model years 1999 through 2002. The list of affected models and years include:

C70 (1999-2002)

S60 (2001-2002)

S70 (1999-2000)

S80 (1999-2001)

V70 (1999-2002)

V70XC (1999-2000)

XC70 (2001)

One important distinction is that this only affects gasoline engines, not diesel.

Volvo will be sending notices to owners of these cars who have not yet had the software upgrade done. They'll be asked to bring their car to a dealer for the repair.

Additional Information:

Anyone with questions can contact the NHTSA's Vehicle Safety Hotline at 1-888-327-4236 or go to SaferCar.gov
Click here to read Volvo's letter to NHTSA.

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