So I got a 6.5 turbo diesel and the heat isn't working well it works every once in a while but there's no pressure. I have to hit the dash for it to kick on but it doesn't work every time. When it turns on there's a cracking noise like there's somthing in there but even if there was just somthing blocking it would still work every time. What could it be?

 

Does it blow cold air? If it does then your problem is probably the blend door actuator.

 

No it doesn't blow cold air

 

If none of the vents blow any air then your problem could be the blower motor, the blower motor resister or the switch.

 

Could you give me an idea of where those are located

 

This
will help.