Hi Grandmak,
I think the recommended pressure is 33PSI. I also had a similar problem with my grand, when checked found that one of the front tires had 2 PSI less air. This caused steering jerk and also slight pull to one side. Try filling air from any petrol pump with digital filling machines. If it still does not help then a short trip to get tires align and balanced is recommended. And Final recommendation Hyundai Service Center, i just got my car's 3rd free servicing done last week. Found that they had adjusted suspensions and kinda improved comfort. Seems like they made them slightly stiff.
Arijit