With the US National Highway Traffic Safety Administration (NTSA) having received as many as 150 complaints about steering problems with the 2009-10 models of Toyota Corolla, the government will Thursday launch an investigation against the Japanese manufacturer Toyota.

Elaborating on the recent steering-related problem, NTSA said that one of the complaints read thus: “When driving on the highway (60+ mph), the vehicle will all of a sudden start to wander back and forth in the lane, for a few hundred yards. Then as quickly as it started, it stops. The wandering has almost created four collisions so far.”

The proposed investigation into the issue, which comes at a time when the complaints-plagued struggling Japanese car giant is already facing problems involving accelerator and braking systems of some Corolla models, will cover nearly 500,000 Toyota vehicles.

The news of the investigation coincides with Toyota’s contemplation about recalling Corolla – the top-selling vehicle in the world and the fifth-ranking best-seller in the US. Since last fall, Toyota has recalled almost 7.86 million vehicles round the world, most of them from the US, because of the unintended acceleration and braking issues.

Meanwhile, noting that Toyota is still trying to figure out the real reason behind the problems, David E. Cole, chairman of the Center for Automotive Research, said that with acceleration, braking and now steering problems, the much-embattled Toyota has “hit the trifecta.”