Civic - Honda :: 2006 - Rough Idle Rumble Strip Sound

My wife drives a 2006 Honda Civic. She just drove back from Vermont - we live near Boston - and on her way back the idle was unusually rough and twice she said it felt as if she was driving over rumble strips, even though she was on smooth pavement. The first time she was going 40 and the second time she was barely moving. She also noted that once, at a stop sign, the car wouldn't slowly move forward when she took her foot off the brake, as it usually does. She had to give it gas. The thing is, the problem is very intermittent.

She says the only thing that is constant is the rough idle, but the engine check light is NOT on.

The last work that was done on the car, about a month ago, was the replacement of the calipers and shoes on one of the brakes. My wife had driven for some time with the squealing noise that indicates you need to change your brake shoes without telling anyone about it. She used the radio fix.