Thank you,
Something wrong with the split(f1iter, idxA, SUBSEP) part.
Result of the script is:
1,ENST00000327169,60240 1 358460,357522,OR4F29
1,ENST00000327169,60030 1 358460,357522,OR4F29
1,ENST00000327169,60090 1 358460,357522,OR4F29
1,ENST00000327169,60120 1 358460,357522,OR4F29...