uvastang

My heat is blowing cold.. The temp doesnt change when I turn from cold to hot .. Its a 93 mustang but the engine is a 87 5.0 I think its something to do with the coolant sysyem because the hoses going into the heater core are warm but not hot and im also able to squeeze on any hose while the engine is running... Any ideas where to start??

AdderMk2

are both hoses to the heater core warming up at the same time?
Have you checked or changed your thermostat recently?
did you make sure you are running the proper coolant to water ratio?

uvastang

its a 50/50 mix coolant.. and im not sure exactly what temp the themostat opens but i did check it when i did the engine swap.. both heater hoses dont really get that hot at all tho.. but all of the coolant hoses do not seem to have much pressure on them.. the heat worked when i had the 4 cylinder in it but ever since i swapped over the 5.0 the heater does not work..

uvastang

Anyone know where I could start looking as to why I dont have heat?

mattdel

I'd be trying to figure out why your blend door isn't actuating.

AdderMk2

blend door issues sounds like its the most reasonable explaination. The lack of pressure though, replace your radiator cap.

uvastang

im able to look up under the dash and see the cable and the rod connected to the door moving.. and like i said the heat worked fine until i swapped engines...

mjr46

I assume you made sure the car is not low on coolant/ radiator full???

Jimk8067

Yeah, low coolant (air in system) or t-stat is stuck open not letting the engine get up to temp.

uvastang

yes i have made sure that the coolant level is full! and im not sure about air in the system or the tstat sticking open but i have removed the tstat when i thought my car wasnt heating up because the gaugue never moved but the tstat worked properly and it turned out to be the sending unit for the gauge so the gauge reads normal but still never heats up and all the hoses do not seem to be firm enough while running.. im not sure where to go from here exactly tho? any step by step checklist i can go by to narrow down my problem??