Definitely check the vacuum. When I bought my JSB ZR1 the NPP was staying open all the time. Turned out the vacuum hose had popped off at the valve. I popped it back on and that was that. 
NPP/bi-modal issues
Thread Starter
Melting Slicks
Joined: Aug 2011
Posts: 2,097
Likes: 81
From: Frankfort,IL
NPP/bi-modal issues
Has anyone had their NPP stay open and it was not the solenoid in the bumper causing the issue? I know there is a module over the rear passenger tire in the cargo area, but so far the solenoid did not solve the issue of the valves staying open. I still have to dig into it and apply vacuum to the actuators and all the other odds and ends to trouble shoot it. Just curious.
Le Mans Master
Joined: Aug 2006
Posts: 5,379
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From: Charlotte NC
Mine was opposite (staying closed 100% of the time) but it was the solenoid...I couldn’t even blow thru it. Hate to state the obvious, but are you blowing fuses? I was blowing fuses every second too.
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Melting Slicks
Joined: Aug 2011
Posts: 2,097
Likes: 81
From: Frankfort,IL
New battery and its always on a battery tender. Once I get the car out of storage and up in the air I can start checking to see if im getting vacuum to the actuators and apply vacuum to them to see if they close. Just curious what everyone else has run into.
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Melting Slicks
Joined: Aug 2011
Posts: 2,097
Likes: 81
From: Frankfort,IL
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Melting Slicks
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I was about to change the solenoid on mine (wasn't getting vacuum), and by mistake dropped it (fumble fingers). Heard a click and it started working again. Never a problem again. If all else is no good, maybe just try tapping it lightly to see if it isn't stuck.
Good luck with the Caravaggio seats...love mine
Good luck with the Caravaggio seats...love mine
Thread Starter
Melting Slicks
Joined: Aug 2011
Posts: 2,097
Likes: 81
From: Frankfort,IL
I was about to change the solenoid on mine (wasn't getting vacuum), and by mistake dropped it (fumble fingers). Heard a click and it started working again. Never a problem again. If all else is no good, maybe just try tapping it lightly to see if it isn't stuck.
Good luck with the Caravaggio seats...love mine
Good luck with the Caravaggio seats...love mine
Thread Starter
Melting Slicks
Joined: Aug 2011
Posts: 2,097
Likes: 81
From: Frankfort,IL
Just to bump my thread, figured it out. Applied vacuum with a mightvac hand pump to the mufflers and they closed. Then I worked my way forward and disconnected the line from the back of the intake manifold that connects to the nipple going back to the mufflers right by the firewall. Applied vacuum and sure as **** the flaps closed. Was just feeling my way around to see if somehow the line came disconnected from the back of the intake and somehow the rubber line right near the connection to the nipple (I dont know what else to call that connection) was rubbing against probably the braided fuel line and it made a hole in the line. Cut the section out and reconnected everything and everything is good!!!!!
Thread Starter
Melting Slicks
Joined: Aug 2011
Posts: 2,097
Likes: 81
From: Frankfort,IL
that was my dilemma when started this thread, replacing the solenoid did not solve my problem. Just glad I was able to fix this, I hate having the flaps open pulling into my house and being a dick to my neighbors with how loud this car is.