I had my EGR valve replaced and now my heater is not running right. It will go cold while I’m driving and when I am at a stop light. I’m in Colorado and really need it to run right. I there a possibility that changing the valve can effect the heating system. I was fine before I too it in.
No. They are not connected. With a 12 year old car, stuff just breaks. Usually at inopportune times.
They may not have properly filled the cooling system after replacing the EGR valve or there could be a coolant leak. Check the coolant level and inspect for leaks.