ported vaccum switch 78nova

C

cnova78

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I have a 78 nova base l6 and I'm swapping out my vacuum lines and system. So I'm cha ginger out my port vacuum switch and apparently my car has 3 . One On Top Of the thermostat housing one on the Lower and another on the side of the engine. I liked online and they only have one listed. Are all three of them The same
 
Have no idea why your car would have 3 ported vacuum switches. Ported vacuum refers to the advance mechanism on the distributor. It is used for emissions purposes as opposed to manifold vacuum. The ported systems are controlled by one switch that is temperature controlled. So which switch does the vacuum line from the distributor connect to, that is the ported vacuum switch. Any other switches you see have nothing to do with ported vacuum. Do you have the 1978 Chasis Service manual, it has a section on emission controls with diagrams. Another thought is if you dont need to have it set up original just run the vacuum line from the distributor to a port on the carburetor or intake manifold that has vaccuum at both idle and at higher speeds.
 
Correction it has two after I looked at the diagram I recognized A part I saw online I couldn't get the phone to upload the stupid pics so here's a quick video
Watch "C nova valves" on YouTube
C nova valves: http://youtu.be/c43_Bn056LQ
Mr.C
 
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I found this diagram for a 1978 six cylinder in a truck and it may be similar. There are three TVS switches, distributor, egr, and EFE . The two on the thermostat housing manifold look the same, do they have the same numbers stamped on them? Why are you trying to change all these sensors? The second link seems to indicate that the distributor and egr use the same part number switch

http://repairguide.autozone.com/zne...00c152/80/07/a3/4e/large/0900c1528007a34e.gif

http://www.ecklersnova.com/nova-ac-delco-thermal-vacuum-valve-1977-1979.html
 
thanks. The diagram I have in my service manual my question is the two valves by the thermostat housing are they the same
 
The reason why I'm changing it the car failed smog on the air part so I'm swapping everything out on the engine related to the air pump lines etc. The one on the top has a part number 335 961 and the other has two sets of stamps on it .it has EC on the blue part and J10 on the bronze part weird
 
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