QuestionI have a 84 300tdt and the center vents are not blowing air, at any setting. Also the defrost option only blows very hot air. Any suggestions as to what to look for?
AnswerTry to locate the mono-valve. On my car it is in the firewall well.
An electrically operated multiple hose valve used to regulate water flow in several directions.
Rather than run the risk of breaking a hose in such a tight location, I replaced the internals and it repaired my problem.
After removing the electrical leads, I removed three screws and just lifted the top off. The plunder came out very easily.
It was 'gunked up' I could have probably cleaned it and reused it, but because I already had the new one, I just installed it.
The second possibility is a vacuum leak. Many of the internal flap under the dash are controlled with vacuum.
Good Luck
Rob
