Question about 1985 Nissan 300ZX

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Vents blow hot air all the time and heater/ac controls do nothing

After having a competnet mechanic shop remove my original engine and install a rebuilt one, everything is good but the ac and heater no longer work. The vents allow engine (hot) air into the cabin all the time and nothing I do stops that. I want to resume normal function of heater, ac and vents. What should I do? I have very little money but I am fairly good mechanically if I have some guidance. In other words, I don't want to go and rip out my dashboard in search of the solution and have no clue where to start.

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I had this problem also, there are some vacuum hoses under the hood near the back passenger side of the the engine bay check for broken or cracked hoses.

Posted on Jun 15, 2009

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I had the exact same problem with my '85 300ZX. Turned out to be a vacuum hose under the dash that had come loose. I noticed that others were brittle and would soon probably crack, so I replaced them all. There is some good info at http://www.thumper300zx.com/z31/vacuum/vacuum.htm


Posted on Feb 01, 2009

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As per your problem mentioned. There are few solved help links to troubleshoot these problems. Go through the list and Click the link below:----

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http://whatisbyme.blogspot.in/2012/05/2000-toyota-avalon-no-heat-on-passenger.html


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