can a leak at the heatercore hose just a small one cause the fans not to kick on . the reason i ask is because i have tried the t-stat and the switch on the fan shrow and both coolant temp sensors . the only way thay come on is with the air or heat turned on. its getting hot and dont want to run the air all the time it pulls alot of performance power from the car with it on all the time.any help is thanks in advance