I had this problem with an old AC Delco FM receiver. Although I was also only having a problem with one or two stations, the antenna was the problem. Try a different antenna before messing with anything else inside. Also, if that doesn't work and you are going to open it up, check the antenna connections inside the case.
HI SIR
WE CAN T MANUALLY TUNE AT 98.2MHZ.
IT SKIP THIS FREQUANCY WHEN SCANNING.
WE HAVE MANY PCBA FOR THIS MODEL SOME PIECES DETECT FREQUENCY VERY GOOD AT SAME PLACE AND SAME ANTENEA,OTHER SKIP IT,AND WE HAVE SOME OLD SAME PCBA THAT WAS DETECT THIS FREQUENCY BEFORE AND NOW SKIP IT TOO.
FOR THIS I THINK THERE S NO ANTENEA OR FREQUENCY PROBLEM
It might be a copy of the scanning FM "radio" I bought for $1.00 at the Dollar Store. It uses a Chinese copy of a Philips TDA7088 FM radio IC that does not work well. The radio came with earphones and a battery so the actual radio was free.