1991 ford f 250 low idle surge and stall
 

HI I am new to this forum but thought I would give it a try I have a 1991 ford f 250 with 302 50.L it will run fine at a 1000 rpm but when it drops under that it will start to surge and then stall I checked the ICA and cleaned it and Know that it working properly I have not done a sweep test on the TPS yet I also know that my fuel press is within spec. what I was wondering is if my sweep test checks out ok is where do I go next if I had a leaking intake gasket would that create the same symptoms or if I had bad grounds could that cause the same thing