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1985 Nissan 720 Z24 Thermal vacuum valve


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I have an 85 720 that is still running great.  Unfortunately I live in California and it fails smog testing.  I traced down the problem to a defective Thermal vacuum valve (TVV).  So the EGR is never being activated.  However, I can't seem to find a replacement anywhere.  Does anyone know where I might be able to locate one?  Or a substitute?  I think the part number is : 14890-N8500.  I've tried the junk-yards in the area and the ones i have found are also defective.  I think the long-term solution is to move out of California...but I'm looking for a short-term solution.  Any help or advice is welcome.   Thanks!

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Rock Auto? 


Want add on here?....  https://ratsun.net/classifieds/category/9-datsun-parts/


Get one from another car or truck that also used it?


Was also used on the following...


'80-'81 A10 HL510

'80-'81 S110 200sx

'84- S12 200sx CA20E

'84- 720 Z24

'84- T11 STANZA



All the TVV does is prevent vacuum advance and ERG vacuum signal from getting to the distributor and the EGR until the engine warms up. If you were to plug the two bottom hoses at the EGR and connect them to it you would defeat the TVV and have advance and EGR even when the engine is cold. I doubt the emissions test includes letting the engine sit till cold and checking that the TVV works. All they want is the EGR working. Try it.

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