LOS ANGELES — Toyota is voluntarily recalling about 75,000 of its much-touted Prius hybrid sedans to fix a computer software glitch that could cause the car's gasoline engine to shut down.

The action, covering about half of the 2004 and 2005 gas-electric hybrids built so far, comes after the National Highway Traffic Safety Administration said it will close an investigation into the problem that eventually resulted in 428 complaints. No accidents or injuries resulted.

"We're satisfied that what they're proposing to do will take care of the problem," NHTSA spokesman Rae Tyson said.

The probe began in May after owners reported cars going haywire — warning lights on the dashboard would suddenly all flash and the gasoline engine would die, Toyota said. The driver was usually able to get the car off of the road on electric power alone and restart it.

It was a rare bit of trouble for a car that has become Toyota's symbol of environmental success. The gas-electric power plant saves fuel and barely pollutes — without major sacrifices in performance.

The Prius was listed last week by the Environmental Protection Agency as the second-most fuel-stingy car, behind Honda's two-seat hybrid Insight.

Prius' problem was traced to a software bug in the car's computer brain, called an electronic control module. Because most new cars have similar systems, repairing the glitch is "fairly routine and not related to the hybrid system itself," said Toyota spokesman Xavier Dominicis.

In some cases, technicians will add grease to seal a transaxle connector that could have caused the same problems.

The fix takes about two hours.

The "special service campaign," as Toyota terms the action, covers Priuses built from Aug. 4, 2003, through Feb. 10, 2005. Owners who aren't sure if their vehicle is covered can call Toyota at (800) 331-4331. Toyota says it will mail notices to affected owners later this month.

Toyota sold 53,991 Priuses in the 2004 model year and 81,042 through September of this year, Autodata reports. The Japanese automaker has vowed to build about 100,000 this year as high gasoline prices lure buyers.

Spokeswoman Allison Takahashi says the wait to buy a Prius can be up to two months.

Last year, Toyota asked some owners to bring their Priuses into dealers as other small glitches popped up. Those included a programming error that made it hard for service technicians to get data from the car, and a faulty engine compartment seal.