I have a Goodman GMP 075-3 FURANCE,the blower jumps on and runs all day and sometimes it jumps on and off all while the A/C COMPRESS IS STILL Running. Same in winter. I changed out thermastat and filter. Its 17yrs old heats and cools great. BLOWER ASKS UP. WHAT TO TRY NEXT WITH LIMITED CASH

I have a Goodman GMP 075-3 FURANCE,the blower jumps on and runs all day and sometimes it jumps on and off all while the A/C COMPRESS IS STILL RUNING. Same in winter. I changed out thermastat and filter. its 17yrs old heats and cools great. BLOWER ASKS UP. WHAT TO TRY NEXT WITH LIMITED CASH

Sounds like the time delay relay for your blower motor is failing--could be loose wire connections.