Carrier Weathermaker 8000 Heat and Cycling Problems

Hello all, First time posting here. My Weathermaker 8000 lights up fine and all burners are lit, but the heat coming out of the vents is warm at best. Filters are new. Air flow is good. But it just doesn't get hot. Every other house I have lived it it would burn your feet if you stand on the vents. This one will barely get your toes warm. Also, it will cycle on and run for about 5-10 minutes and then cycle off. After going off, it will come back on 30 seconds later. It will just keep doing this as the house never warms up to the set temp. Flame sensor is clean, I even tried cleaning it more just in case. That is about the only thing I know to check. Please give me more ideas.