General Motors CEO Mary Barra finishes her testimony before a Congressional subcommittee last week.

The company is recalling 2.19 million of the same models to fix a problem that allows keys to be removed from ignitions that are not in the "off" position.

Replacement parts for cars at the center of a massive General Motors recall for defective ignition switches began arriving at dealerships across this country just this week. If car owners have already gotten repairs made, they'll need to make an additional trip to their dealerships. On Thursday, General Motors said there's another safety problem plaguing the same vehicles.

The company is recalling 2.19 million of the same Chevrolet Cobalt, HHR, Saturn Ion, Sky, Pontiac G5 and Solstice models to fix a problem that allows keys to be removed from ignitions that are not in the "off" position.

In at least one case, a vehicle rolled away in a parking lot and resulted in a crash and injury, according to GM, which said it is aware of "several hundred" complaints about keys coming out of ignitions. The company will fix the ignition lock cylinders to prevent the problem.

This is a separate problem than the one allowing ignition switches in the same models to inadvertently move from the "run" to "accessory" positions, which can turn off both the engine and airbag systems. That defect has led to 13 deaths, and subsequently, Congressional inquiries into why the company didn't recall affected vehicles sooner.

Earlier Thursday, GM announced it has suspended two senior engineers – with pay – who oversaw changes in ignition-switch designs. Although the company did not name the two, Bloomberg News reported they were Ray DeGiorgio and Gary Altman.

During Congressional hearings last week, Sen. Claire McCaskill (D-MO) alleged that DeGiorgio had perjured himself while testifying in a lawsuit related to a crash caused by the faulty ignition switch, and expressed disbelief that he had not yet been fired.

"This is an interim step as we seek the truth about what happened," GM CEO Mary Barra said about the suspensions Thursday. "It was a difficult decision, but I believe it is best for GM."

Before removing the key from the ignition, GM says motorists should ensure their cars are in the "park" position or, in manual cars, have the emergency brake on until the cars are repaired. In the case of the ignition-switch recall, GM says drivers must remove all keys from their key rings until the cars are fixed.

Overall, the company has issued six recalls in the past four weeks that affect 4,258,687 cars, including Thursday's recall.

While GM has maintained the cars are safe to operate in that instance, it has also said there's a heightened risk driving on rough roads and other potentially jarring conditions. A US District Court judge in Texas is weighing a request to ground the entire fleet of affected cars until repairs are made. Last Friday, she said she did not yet have enough information to make a decision.

GM announced the ignition-switch recall in February and has twice expanded it to include more vehicles. Overall, the company has issued six recalls in the past four weeks that affect 4,258,687 cars, including Thursday's recall.

The company revised financial figures and said it expects to spend $1.3 billion on recalls in the first quarter of 2013. That's up from previous estimates of $750 million.

"The extent, and cost of GM's ignition-switch recall has grown dramatically in the past few weeks," said Karl Brauer, a senior analyst with Kelley Blue Book. "Much of this stems from GM's desire to comprehensively address all aspect of the recall, though there's also growing concern over potentially deceptive or criminal behavior that could result in government fines."

Pete Bigelow is an associate editor at AOL Autos. He can be reached via email at peter.bigelow@teamaol.com and followed on Twitter @PeterCBigelow.