link to buy expansion valve
https://amzn.to/2RvioDI
Nissan Murano 2003 – 2007 A/C Fix ( Expansion Valve )
this video will help you to give you an idea to where and how to remove the expansion valve on a Nissan Murano ,
the symptoms I was getting on my Murano was this
1- cold air only worked sometimes
2- compresor was making a small humming sound
3- no pressure sometimes on the a/c line
after I replace the expansion valve the problem was fix and now it blows cold all the time.
For business inquires email: FixitFelix529@gmail.com
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The first thing you should've done is to check the system properly before buying anything.