No Heat, need advise

[Snapper17]

Hi there, I recently bought a 'new' 1990 Lincoln Continental and realized no heat is coming out of the vents. It has Auto climate control that seems to be working fine, since the fan only starts when the engine is warm, but only cold air is coming out.

So I am thinking the Thermostat must be working fine, or the fan would never start. To me, and I am no expert, either the heater core has failed (by the way there is no coolant in the car on the carpet), or the hoses are plugged.

With that, I have been reading on flushing the cooling system.

Any advise? Anyone can help me locate the hoses that run to the heater core?

Thanks in advance for your help, it is greatly appreciated.

 

[purelux]

Is it on automatic, have you tried hitting just the defrost or floor button? Also it could still have a bad thermostat or clogged coolant lines or radiator & or heater core but most likely its in the hvac itself. Since most people only change anything besides engine oil and winshield washer fluid when something breaks I'd flush the coolant. Make sure and don't just drain the radiator or you won't get alot of the fluid and use distilled water to refill to prevent mineral deposits. A shop like monroe, ford dealer etc... or most anymore do a t-tech or similar total fluid exchange. My brother had a old olds ciera and it took 3 flushes by monroe to get it clean.

 

[ground_zero298]

Being a 90 and the cost of replacing a heater core. I would check to see if someone already bypassed the heatercore when it started leaking. You should be able to grab all the hoses under the hood and follow the warm hose untill you find where it goes cold. Or maybe a vacuum line fell off? And I'm not sure what your heater hose looks like but mine looks like a mini radiator hose, one going into the firewall and one coming back out.

 

[Snapper17]

Thanks for the reply.

The previous owner sais he did not have problems with the heater, but the car sat in a parking lot for something like 6 months. I will verify the hoses to and from the firewall.

I will keep everyone posted on the results

 

[purelux]

My friend has a 90's civic that sat for like 6-8 months and everything worked when parked. When we fired it up the radio's removable faceplate needed the contacts cleaned before it worked. The automatic floor shifter was like dragging it through the mud. As well as the brake system now seems to have a vacume leak. The car "stops" but the rpms jump around and the pedal goes to the floor when the pedal is depressed (un-driveable). In your case Its possible it is just the hvac "module" itself it and have a vacume leak or corroded connection. Normally automatic ac systems will always run in heat mode. For example in automatic they will switch to vent if the psi of the refrigerant drops or a similar problem to prevent a worse condition. Though normally they will usually run on heat, vent or defrost. I would suggest changing the thermostat and having the coolant "cleaned and exchanged." Most likely the car hadn't had a change in quite a while and even if so sitting that long changing it could easily allow corossion or gunk to build.