Car swerving slightly

Hello, this is a tough question for a forum like this. It is suggesting there is a dangerous problem you are experiencing that could result in an accident. No level of suggestion here could be helpful -- you desperately need to seek the guidance of a technician local to you, who could experience the concern you are actually having first hand, and then work to resolve it. This is serious business, and I hope you will regard it as such, for your own safety -- and the safety of those on the road around you.