A year ago, I had a used engine replacement, new thermostat and all parts, from intake manifold and all needed headgasket replacement. Now, my car is running hot once again. Some guys that stopped to help me said that my heater core was bad, because there was leakage in the passenger floorboard, and I actually thought I felt droplets of coolant burning my leg until I pulled over. QUESTION: Should they have replaced my heater core when they did this headgasket repair a year ago? I don't see that part listed, and they offered me no warranty at all because the part was used, and they sent the head out to a machine shop for repair. I paid 808.60 for this work, but I do not feel confident taking my car back to this shop. I have read the info here on heater core replacement, but I would like a professional opinion. Thanks.