HELP! No suction/vacuum! NPP Switch to Fusions
Thread Starter
Burning Brakes
Joined: Sep 2011
Posts: 960
Likes: 7
From: Denton, Texas
St. Jude Donor '12
HELP! No suction/vacuum! NPP Switch to Fusions
I have a 2008 that came with the factory NPP exhaust. I installed a old school headlight actuator button on the foot rest to control the exhaust and tapped into the fuse area (i.e. homemade M2W).
I recently switched my NPPs for a set of Fusions. When I reconnected the vacuum lines (stock NPP) they no longer provide suction and the Fusions are stuck in the open mode.
Anybody ever seen or heard this or possibly know what the problem is?
Thanks in advance, Austin
P.S. I've checked the connections and the fuses. Both are good!
I recently switched my NPPs for a set of Fusions. When I reconnected the vacuum lines (stock NPP) they no longer provide suction and the Fusions are stuck in the open mode.
Anybody ever seen or heard this or possibly know what the problem is?
Thanks in advance, Austin
P.S. I've checked the connections and the fuses. Both are good!
Moderator emeritus
Joined: Jun 2001
Posts: 18,599
Likes: 3,951
From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
OK you did 2 mods
Do you have the fuse in correctly in the foot well? Do you see continuity through the switch for the power. No power, no vacuum.
If you get past that then you can check for a vacuum loss.
Elmer
Do you have the fuse in correctly in the foot well? Do you see continuity through the switch for the power. No power, no vacuum.
If you get past that then you can check for a vacuum loss.
Elmer
Melting Slicks
Joined: Mar 2007
Posts: 3,327
Likes: 166
From: Summerton SC
Tech Contributor
Sounds like maybe the different actuators (stock NPP vs Fusion) could require a different vac pressure, or are they supposed to work together? Check with your dealer and let us know. So how do those Fusions sound compared to the previous stock?
Thread Starter
Burning Brakes
Joined: Sep 2011
Posts: 960
Likes: 7
From: Denton, Texas
St. Jude Donor '12
1) I don't know how to check the actuators on the fusions. It is possible they are bad. Any ideas on how to check them.
2) I "believe" the fuse and everything is good. I don't have an amp meter right now so I cant check the power. May have to invest in one at auto parts store.
3) What exactly do I need to do to check the vacuum? The switch worked fine for months with my NPP then I switch over and from the start the fusions wont do anything.
4) The Fusions aren't really any "louder" but the "tone" is deeper and much better in my opinion. Very little back popping on deceleration. Hopefully will get some OBX headers without cats soon to help "promote" that exhaust note. I can't give any info on the quiet mode because they won't work properly
2) I "believe" the fuse and everything is good. I don't have an amp meter right now so I cant check the power. May have to invest in one at auto parts store.
3) What exactly do I need to do to check the vacuum? The switch worked fine for months with my NPP then I switch over and from the start the fusions wont do anything.
4) The Fusions aren't really any "louder" but the "tone" is deeper and much better in my opinion. Very little back popping on deceleration. Hopefully will get some OBX headers without cats soon to help "promote" that exhaust note. I can't give any info on the quiet mode because they won't work properly
Moderator emeritus
Joined: Jun 2001
Posts: 18,599
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
With the car running, pull off one line from an actuator and see if there is vacuum on the line. If there is, the actuator you took it off is "open" and leaking. If no vacuum on the line, plug it back and remove the other line from the other actuator. If you have vacuum, then the 2nd actuator is leaking. If you don't have vacuum, then the loss of vacuum is toward the engine.
Elmer
Elmer
Race Director
Joined: Mar 2005
Posts: 10,399
Likes: 25
From: Austin Texas
With the car running, pull off one line from an actuator and see if there is vacuum on the line. If there is, the actuator you took it off is "open" and leaking. If no vacuum on the line, plug it back and remove the other line from the other actuator. If you have vacuum, then the 2nd actuator is leaking. If you don't have vacuum, then the loss of vacuum is toward the engine.
Elmer
Elmer
Thread Starter
Burning Brakes
Joined: Sep 2011
Posts: 960
Likes: 7
From: Denton, Texas
St. Jude Donor '12
I think its the switch. I put the stock fuse back in and got vacuum. Then reconnected my switch then nothing.
However, I put the stock fuse back in again and nothing. I going to work on the connections more this evening but I don't know whats going on.
However, I put the stock fuse back in again and nothing. I going to work on the connections more this evening but I don't know whats going on.
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Thread Starter
Burning Brakes
Joined: Sep 2011
Posts: 960
Likes: 7
From: Denton, Texas
St. Jude Donor '12
I'm feeling suction from both sides but it is minimal. I even replaced the stock fuse and it won't close them. I'm just going to have to suck it up and take it to a performance shop and get a diagnosis.
