I have a 1983 cutlass supreme and My heat does not get hot just warm at best and I am running out of things to fix. I have replaced the blower motor, blower motor resistor, radiator, heater core, top hose from the radiator to the thermostat housing and bottom hose from the radiator to the water pump and new thermostat as well and just two days ago I flushed the radiator. I am running out of ideas please help. It's freezing outside

 

First question: Are both hoses to and from the heater core hot? If so, then why replace any parts of the cooling system?

Second question: Does the fan blow air out the vents? If so, why replace the blower motor and resistor?

Have you looked at the heater blend door bellcrank behind the glovebox? Remove the glovebox liner and you'll see a plastic bellcrank. This operates the heater blend door that mixes hot and cold air in the HVAC box based on the TEMP lever on the control head. This bellcrank breaks, preventing the blend door from moving. Unfortunately, replacements are no longer available. If the break is just the pin that the control cable fits over, you can usually use a small machine screw and nut to replace it.

 

Does your car have a heater control valve in the hose going to the heater core? If so, it could be malfunctioning.

 

The heater control valve on these cars is normally open and requires vacuum to close. Being stuck closed is an unlikely failure mode at best, and again, if both heater hoses are hot (a VERY easy test to run with your hand), the valve is not the issue.

 

Yes both hoses are hot and the reason for replacing those parts are because they went out in the summer. Heater core started leaking coolant on the passenger side floor and the radiator was just super old.

Yes it does but the blower motor stopped working and the resistor connector was melted so that's why I replaced those to as well.

No I have not looked at that. I'm still learning. Ok thanks I will look for this today.

 

I was actually wondering if I needed to replace that. The only reason why I have replacing everything is because the person I got it from had it just sitting for almost 20 years in a barn.

 

The only purpose of this valve is to close when the A/C is set to MAX COLD. It will not affect your heat issue.

 

OK then thank you so much. That eliminates that out the equation. So does vaccum lines cause a heat issue?

 

What, EXACTLY, is your heat issue? If the HVAC blows air at sufficient force through the vents you select, then the ONLY thing that can affect heat is the blend door, which is cable operated. The vacuum is used to switch from heat to vent to defrost outlets, but temperature is controlled ONLY by the cable and the blend door.

 

It gets warm at best in the car. Where as two winters ago it would get super hot. The vents are not that strong when it blows and on the passenger side the vents don't blow at all. It just fills warm. So I should try replacing the blend door? I think I found it on ebay.

 

Is this it?

 

Go re-read post #2. It isn't the blend door that goes bad, it's the bellcrank. In any case, do some troubleshooting before buying parts. Pull the glovebox liner out and look at the parts.

 

Looks like it. Good to see it's available again. In any case, look at the old one first. It might be something as simple as the cable came off the pin.

 

OK thank you so much and if anyone needs one there on ebay for like $27.