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Posted (edited)

Hi all, I just joined the forums. I bought a 77 280z a couple of days ago and I'm having trouble passing emissions. The previous owner installed a megasquirt EFI which wasn't really the issue during the test. However, some vacuum lines are missing.
 

The EGR valve isn't connected to anything and the vacuum line diagram shows that I must have a BPT valve, which I don't. Would it be ok if I connect the EGR valve directly to the intake manifold?

EGR valve photo


The other issue is the purge valve on the carbon canister isn't connected to anything either, form what I understand, it should be going into the throttle chamber where you can see that it's plugged in

 Throttle chamber photo

 

Carbon canister photo
Thanks!

Edited by smsms
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What type of test are you trying to pass?  Just idle, or idle and 2500 RPM?  Or some sort of visual?

 

The hoses and devices are shown and described in the Emissions chapter of the FSM.

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Posted (edited)

What did emissions fail you on? I have to do Arizona emissions (Tucson) and had no real problems with my 280z with all emissions removed. I failed the second time, but that was because of the liquid oil coming out of the tail pipe...

 

Post up your emissions sheet, that'll give us a better idea where to start

Edited by ZHoob2004

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Sounds like they actually do some inspection up there. Here they just look under the hood to make sure you have an engine. My EGR and evap were completely disconnected just like yours. If you just want to pass, I think you can just plug the egr valve into any port on the intake manifold and follow the diagram for the evap can. I'm not really sure about the "BPT valve." I'm pretty sure it has something to do with when EGR kicks in, but I don't know if it will have a negative effect on performance or emissions, but it'll probably get you past the visual just like that.

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I spent all night researching this, apparently the BPT valve controls how much vacuum the EGR valve receives, if I connect it to the intake manifold directly I guess the EGR will stay open. I dont know if that will affect the engine performance in a any way but if it gets me through emissions, i'm willing to try I guess.

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1 hour ago, smsms said:

I spent all night researching this, apparently the BPT valve controls how much vacuum the EGR valve receives, if I connect it to the intake manifold directly I guess the EGR will stay open. 

 

Where?  

image.png.9d83adb69d1a3082ebc5b97c7ef8d4dd.png

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I'm assuming the thermal vacuum valve is the one with the red cap in this photo5ab4105e4ca03_1521690878639664280807_1521690898891(1).thumb.jpg.3c85934ff3b90e5be3be0922d5833d94.jpg

 

if I bypass the BPT valve the the EGR valve will actually stay closed. since there's no BPT valve therefore it's technically always "open". 

 

Anyways I'm just spitballing here. I'm probably gonna delete the EGR after I pass emissions, so I just need it to look like it works and not do any damage in the process.

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