NPP flap not working? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

gbu27 · 10-05-2015, 04:35 PM

I have searched quiet a bit and cannot find any helpful threads. I know the flap is open during startup and at idle. I have been trying to see and make sure mine is closing when it hits 1.2k to 1.5k and I am not seeing my flaps move at all. Does anyone have any tips on where to look for problems? I did pull the F8 fuse out once, but put it back in. Any trouble areas for a vacuum leak possibly? I'm just not sure where to look to fix this.

Stephen12ZL1 · 10-05-2015, 05:36 PM

when you rev the engine at idle the flaps will close at rpms barely above idle. You need to pull the F8 flapper fuse and see if the flaps open and close when the fuse is placed in the appropriate slot.

SlingShot · 10-05-2015, 05:47 PM

Check the fuse, if it's blown it will act the same as removing it.

gbu27 · 10-05-2015, 06:19 PM

I have checked the fuse, actually put a multimeter on it and ohmed it out. It checks good. I tried checking the vacuum, but have no idea how strong it should be I felt almost nothing when I tried each line at the flaps. I have read the vacuum for it is the small line off the supercharger snout, went back off it and also checked vacuum again right where the rubber line connected to a hard line at the back of the engine.

Nor Cal ZL1 · 10-05-2015, 08:06 PM

They stick closed. I had to adjust mine.

gbu27 · 10-05-2015, 08:12 PM

Quote:

Originally Posted by Nor Cal ZL1

They stick closed. I had to adjust mine.

Problem is I'm not seeing them close at all. I will have to go get some stuff tomorrow to help me search for a vacuum leak. I thought a vacuum pull would be fairly noticeable by plugging a line with my finger, but I feel pretty much nothing.

CamaroDreams76 · 10-05-2015, 08:48 PM

I thought they closed at 2k-3k.

Nor Cal ZL1 · 10-05-2015, 09:31 PM

Quote:

Originally Posted by gbu27

Problem is I'm not seeing them close at all. I will have to go get some stuff tomorrow to help me search for a vacuum leak. I thought a vacuum pull would be fairly noticeable by plugging a line with my finger, but I feel pretty much nothing.

Ah sorry I was using my phone and missed that. You should be able to reach the lever and move it back and forth to make sure it is free. I would suspect the vacuum signal to be strong also, they close with some authority, thus mine were sticking closed. I suspect there is a vacuum source that is switched up by the intake manifold somewhere. best of luck.

DrkPhx · 10-05-2015, 09:39 PM

You can check the vacuum lines on the small canister by the passenger side muffler and on each muffler on the actuator.

gbu27 · 10-06-2015, 07:03 AM

Yea, I have checked both, they seem to move freely by hand, no binding or bad resistance. I have checked most of the lines in the back around the canister and all seem good.
To be honest maybe my NPP has been having an issue for a while, the whole reason I having issues is a just bought a forza 3 way controller, hooked everything up and valves wouldn't close. I thought maybe it was a defect with the forza possibly but I wanted to make sure it wasn't the car. I hooked the car back up to stock configuration and still not seeing the valves move. I thought it was working normally before I tried to hook up the forza but now I am not so sure.

gbu27 · 10-06-2015, 10:44 AM

I just found the problem about 30 minutes ago. I went to town and bought a mighty vac and tested the flaps, then checked a vacuum at the line going to the canister/solenoid at the rear and found no vacuum, I then went to the front of the engine and disconnected at the rubber/metal line connection and had a vacuum. So that narrowed it down to the long metal line, I went back to the rear and traced the line forward and found the rubber/metal line disconnect had come off at the back, its on the driver side just forward of the pumkin. After that I was confident it would work, hooked the forza 3 way controller up and it works amazing, very excited to have it working. I have no idea how long that line was like that.

jayno20 · 10-06-2015, 11:35 AM

Quote:

Originally Posted by gbu27

I just found the problem about 30 minutes ago. I went to town and bought a mighty vac and tested the flaps, then checked a vacuum at the line going to the canister/solenoid at the rear and found no vacuum, I then went to the front of the engine and disconnected at the rubber/metal line connection and had a vacuum. So that narrowed it down to the long metal line, I went back to the rear and traced the line forward and found the rubber/metal line disconnect had come off at the back, its on the driver side just forward of the pumkin. After that I was confident it would work, hooked the forza 3 way controller up and it works amazing, very excited to have it working. I have no idea how long that line was like that.

Good info. Thanks for posting what fixed the problem for others possibly having a similar issue.

12oclockshadow · 05-07-2021, 09:13 PM

Quote:

Originally Posted by gbu27

I just found the problem about 30 minutes ago. I went to town and bought a mighty vac and tested the flaps, then checked a vacuum at the line going to the canister/solenoid at the rear and found no vacuum, I then went to the front of the engine and disconnected at the rubber/metal line connection and had a vacuum. So that narrowed it down to the long metal line, I went back to the rear and traced the line forward and found the rubber/metal line disconnect had come off at the back, its on the driver side just forward of the pumkin. After that I was confident it would work, hooked the forza 3 way controller up and it works amazing, very excited to have it working. I have no idea how long that line was like that.

I need to check this on my car. Bought mild 2 wild and it's not working flaps dont close at all. Put f8.fuse back in like stock and nothing. So Ill be checking these.

608RS · 05-07-2021, 11:13 PM

Quote:

Originally Posted by gbu27

hooked the forza 3 way controller up and it works amazing, very excited to have it working. I have no idea how long that line was like that.

glad you got it fixed. and just a friendly FYI i see you hooked up the Forza 3-way controller. if you used the fuse-tap that kit comes with, that controller will be pulling a constant 12v source and can easily drain your battery in a matter of 10 days if you don't start/drive the car. you may want to get in the habit of turning off that contoller (big red circular button on the box itself) if you don't plan on driving the car often..and then turning it on should you want to drive & use it. ask me how i know all of this

lol

10-05-2015, 04:35 PM	#1
gbu27 Drives: 2013 ZL1 Join Date: Jun 2015 Location: NC Posts: 106	NPP flap not working? I have searched quiet a bit and cannot find any helpful threads. I know the flap is open during startup and at idle. I have been trying to see and make sure mine is closing when it hits 1.2k to 1.5k and I am not seeing my flaps move at all. Does anyone have any tips on where to look for problems? I did pull the F8 fuse out once, but put it back in. Any trouble areas for a vacuum leak possibly? I'm just not sure where to look to fix this.

10-05-2015, 05:36 PM	#2
Stephen12ZL1 Drives: '21 ZLE A10 Join Date: May 2012 Location: Mechanicsville, VA Posts: 6,808	when you rev the engine at idle the flaps will close at rpms barely above idle. You need to pull the F8 flapper fuse and see if the flaps open and close when the fuse is placed in the appropriate slot. __________________ '21 ZLE A10 Wild Cherry PDR 2:00.78 VIR Full 10.68@131.69 1.68 60' '17 ZL1 A10 Mosaic Black PDR/Nav 2:03.08 VIR Full 11.003@129.2 1.75 (sold) '15 Z/28 #325 Black a/c & stereo. 2:10.1 VIR Full (sold) '12 ZL1 A6 Black 10.52@131 1.55 60' 2:13 VIR Full (sold)

10-05-2015, 05:47 PM	#3
SlingShot Drives: 2012 ZL1 - #670 Join Date: Jun 2009 Location: Seminole, Fl. Posts: 8,009	Check the fuse, if it's blown it will act the same as removing it. __________________

10-05-2015, 08:48 PM	#7
CamaroDreams76 Tri-County Camaro SWFL Drives: 2013 IOM 2SS/RS/1LE Join Date: Apr 2013 Location: South West FL Posts: 3,079 View My Garage	I thought they closed at 2k-3k. __________________ Just bolt ons........ https://www.camaro5.com/forums/showthread.php?t=343023

10-05-2015, 06:19 PM	#4
gbu27 Drives: 2013 ZL1 Join Date: Jun 2015 Location: NC Posts: 106	I have checked the fuse, actually put a multimeter on it and ohmed it out. It checks good. I tried checking the vacuum, but have no idea how strong it should be I felt almost nothing when I tried each line at the flaps. I have read the vacuum for it is the small line off the supercharger snout, went back off it and also checked vacuum again right where the rubber line connected to a hard line at the back of the engine.

10-05-2015, 08:06 PM	#5
Nor Cal ZL1 Drives: 2013 ZL1 M6 Join Date: Oct 2013 Location: Nor Cal Posts: 1,825	They stick closed. I had to adjust mine.

10-05-2015, 09:39 PM	#9
DrkPhx Drives: 2013 Triple Black ZL1 / 2006 TB SS Join Date: Feb 2011 Location: MN Posts: 2,250	You can check the vacuum lines on the small canister by the passenger side muffler and on each muffler on the actuator.

10-06-2015, 07:03 AM	#10
gbu27 Drives: 2013 ZL1 Join Date: Jun 2015 Location: NC Posts: 106	Yea, I have checked both, they seem to move freely by hand, no binding or bad resistance. I have checked most of the lines in the back around the canister and all seem good. To be honest maybe my NPP has been having an issue for a while, the whole reason I having issues is a just bought a forza 3 way controller, hooked everything up and valves wouldn't close. I thought maybe it was a defect with the forza possibly but I wanted to make sure it wasn't the car. I hooked the car back up to stock configuration and still not seeing the valves move. I thought it was working normally before I tried to hook up the forza but now I am not so sure.

10-06-2015, 10:44 AM	#11
gbu27 Drives: 2013 ZL1 Join Date: Jun 2015 Location: NC Posts: 106	I just found the problem about 30 minutes ago. I went to town and bought a mighty vac and tested the flaps, then checked a vacuum at the line going to the canister/solenoid at the rear and found no vacuum, I then went to the front of the engine and disconnected at the rubber/metal line connection and had a vacuum. So that narrowed it down to the long metal line, I went back to the rear and traced the line forward and found the rubber/metal line disconnect had come off at the back, its on the driver side just forward of the pumkin. After that I was confident it would work, hooked the forza 3 way controller up and it works amazing, very excited to have it working. I have no idea how long that line was like that.