Kinda hard to help you without more info. Have you shut your blower off and felt around the heat ducts for heat. Could you have one of those CA emission setups where you have two or three CATs under the car and is one of them heating up? I have a '84 500sl and never notice excess heat on the floor boards unless the heater was running full blast.

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I really gets fun when they all don't run

84 500SL
99 Jeep XJ
93 Jeep YJ
03 Custom Softail