I have a 1997 Dodge ram 1500 318/5.2L. I'm having problems with the heater. It blows cold and times and hot sometimes. I changed the water pump and the thermostat awhile back so i don't believe thats the problem. Can anyone help me out with this?

 

I'm not sure but theirs some door in the system that sticks...there is a lot of recent threads asking about this if you use the search funtion and search no heat or heater you will get your answers.

 

I have to take my dash apart to get to the blend door that was sticking half open and that solved my problem.

 

Blend door shouldn't matter if it's on floor or vent heat b/c the a/c compressor is not engaged, unless it is getting outside air somehow.

 

If you just replaced water pump and tstat you probably have an air pocket in the system. Take the radiator cap off and let it run.

 

....with front end on ramps or facing uphill.

 

You don't have to put her on ramps or hills, just pull the cap n squeeze the upper radiator hose until no more bubbles come outta the radiator...while she's warm of course.