heater

[steve53]

i have a 94 vette and the heater wont get hot. any help will be apprecitated. thanks

 

[vetteoz]

What is engine coolant temp?
Start by confirming you have hot coolant into and out of the heater core.Core might be blocked and need flushing out
If you do have flow then problem most likely with the things that control the actual temp .
Air blend door / motor is the most common

 

[steve53]

What is engine coolant temp?
Start by confirming you have hot coolant into and out of the heater core.Core might be blocked and need flushing out
If you do have flow then problem most likely with the things that control the actual temp .
Air blend door / motor is the most common

thanks for the info, i have checked the flow from the heater core and it is clear, but seems to be not much water in the hoses. i need a service manual for a 94 vette, any sugestions. thanks steve53

 

[boomdriver]

thanks for the info, i have checked the flow from the heater core and it is clear, but seems to be not much water in the hoses. i need a service manual for a 94 vette, any sugestions. thanks steve53

FSM are readily available on FeeBay for $75 used, $150 new.

If the thermostat is working, then the water pump forces water to the heater. If water is not making it that far, the thermostat might be stuck open allowing the easiest return for the water (to the rad) and diverting little to the heater. If the car takes a long time to warm up, ck the T-stat.

the only other thing that can cause reduced flow to the heater lines is a plugged intake manifold orifice. Most cars have an orifice in the intake where the heater hose connects, so the intake keeps water backed up to fill the top end of the engine in an attempt to eliminate hot spots and dry spots. This also helps smaller hoses because they require a higher pressure than the larger radiator hoses. If the orifice has closed off from corrosion that could account for reduced flow to the heater. Otherwise, if hot water makes it to the heater, and flows thru freely, the core is being heated but its not being blended with cabin air. That would be the air-mix door inside the cabin.