We have done a complete tune up and i still don't have heat we have replaced the talder switch could it be the heater coil because the hoses are not warm either

To by pass the heater coil, you must connect the two hoses going into the heater coil. Did you do this? or did you just plug one hose line? best to replace heater coil if it is leaking to get heat working in winter.

Probably the heater core. I backflushed my Dodge Dakota and that fixed the problem. Determine which hose is the supply and the rerurn hose. Take them both loose and back flush with your outside hose pipe. Do NOT turn the hose on full blast you could damage the heater core. I opened my hose bibe 1 turn open after fitting a connection to the heater hose. I back flushed, then forward flushed and back flushed a 2nd time. I saw it done on You Tube. Fixed my Dodge! Blows HOT air now!!

Bad coolant flow. check for low coolant, also a thermostat could be restricting proper coolant flow. If coolant is full in the radiator than touch your upper radiator hose to see if it is hot. If their is proper coolant level and engine is warmed up to temp and radiator hose is cold replace your thermostat.

Check to make sure vents are not clogged,below window by wipers check that and vents from dash going down,If not plugged then probably your heater core or heater blower motor may be shot or weak,you need a Haynes manual to check these if you are not familiar with where these are located at.Haynes manuals can be bought at most auto parts stores

Sounds to me like your heater core is clogged. and it may have nothing to do with the tune up. Also if it has a miss now it is because you got water/coolant on your coil right below the hose where it goes into the fire wall. Get a new coil as well.

Do a complete cool/heating overhaul of the system.That is radiator and hose check out.

May be just a bad crank sensor or ign. module.

There should be a thermal coil in it. I know that mid 90's dodge trucks had it mounted under a cover in the engine compartment by where the heater coil on the passenger side. It's about 2 to 3 inches long. Check on that it actually regulates the heat from your heater. Also check for any antifreeze leaks or sweet smell from your heater, this will be the first signs of it being the heater coil.

if the heater hoses are hot on both sides(indicating the engine is at full temp) and you feel the heat controller in dash is working properly, i would suggest disconnecting both heater hoses and backflush heater core with decent amount of pressure. if this improves condition but does not solve completely, heater core replacement is necessary.

Where the rubber hose goes into the heater, there should be an air switch that opens an closes a shut off to the heater coil try it manual it should open an close by hand