The heater control valve

@leeparker66 ,Lee, If your 1999 Lincoln has heater control valve it will be installed in one of the heater hoses in the engine compartment, normally upper hose, closer to the firewall where heater hose connects to the heater. Find below a link to replacement part to enable you to see what it looks like and 2nd link is on trouble shooting heat issues. Your car may not have a HCV and may be temperature blend door motor issue instead. To replace it the instrument panel may have to be pulled back. Not an easy or fun job. Good luck.

I hope this helped you out, if so let me know by pressing the helpful button.

http://www.partsgeek.com/mmparts/heater_...

https://www.2carpros.com/questions/linco...