N249 removed...now DV flutters

[SeKKeY]

I did the N249 removal/bypass just as explained in the writeup a few threads down. However after, my diverter valve will flutter when i get off throttle (anywhere higher than 5psi, otherwise its normal). Any help to what causes this? My DV is hooked up in reversed position, and the vacuum line is directly attached to the intake manifold as per directions. The N249 is looped to itself. Any troubleshooting tips? DV going out? switch DV orientation? I don't want to run it too long like this because its probably bad for the K04.

[7speed]

It is normal for your dv to flutter under partial boost. If it flutters under full boost you have a problem.

That is what it reads for my Spltr valve.

[initiala4]

Mmmm I wouldnt install it reverse though, but I remember when my DV flutters, it means I got a vacuum leak because my guage would read funny.

[SeKKeY]

i have 21-22 inHg vacuum at idle and 25 inHg in gear... but my max boost is about 16-17 psi (should be 18-21 psi for APR K04)..if the vacuum is fine but the boost is lower, can there still be a leak?

[antz]

i have 21-22 inHg vacuum at idle and 25 inHg in gear... but my max boost is about 16-17 psi (should be 18-21 psi for APR K04)..if the vacuum is fine but the boost is lower, can there still be a leak?

i had the same problem... doing a boost leak check..i found that the vac line on my DV was torn.... vac was fine..boost was lower.

[Papachristou]

i had the same problem... doing a boost leak check..i found that the vac line on my DV was torn.... vac was fine..boost was lower.

i had the same problem.. only boosting 18psi on 1+...did boost test and all kinds of BS.. DV was torn

[A4ringedONE8T]

What spring in the DV?

[widgget]

i guess sit would depend on the DV, i don't know how a piston DV would function correctly if you had it in reversed since the pressure would only push on the side of the piston and not the bottom which is required to open it. I guess if this was the case though then the DV would never open which is not what you are experiencing.

[SeKKeY]

APR R1.so no adjustable spring inside. i believe it is a diaphram type also, but im going to check for boost leaks/switch it around today

[BNZ TOY]

Sorry, but how does the N249 removal/bypass cause this? Has it been confirmed?

Possibly just a coincidence that your APR R1 is going bad?

[phantom b6]

I have the same DV and I don't have this issue. Perhaps the DV diaphragm has torn.

[gdawg'05a4]

If you can, swap the lines back to the way they were and confirm if the same thing happens.

[widgget]

the 249 removal is removing the valve that controls the pressure to the top of the DV holding it closed along with the spring pressure. this causes full pressure from the manifold to be constantly holding the DV shut and in turn allowing you to hold boost longer since the DV isn't opening. this shoudl not create a fludder unless you had a very light spring in the dv but it's not changable in the R1. like it was mentioned, it sounds like you have a rip in the diaphragm.

Sorry about my previous post, i can see how a diaphragm dv would function in both directions, i just assumed it was piston since thats what i have :P

[inaforest]

I don't mean to change the subject, but does bypassing the n249 decrease the life of the engine?

[F16HTON]

The N249s sole purpose is to reduce flutter.

[whiteUSPflow]

your not suposed to install that DV in the opposite way since it is a diaphram DV and it will tear. they have a life time warrenty so go to the shop you got it from and get a new one and install it the correct way.

[Capt. Obvious]

^^^ Like he said, don't install diaphragm DVs in the "reverse" position. That should help your problem.

[Killerteve]

What is bad about flutter? I used to get it with my K04 and Forge 007 but I just thought that's how it sounded with a aftermarket TIP and intake. Didn't have any vacuum leaks and still held strong boost, 26 spike, 22 hold on Revo stg. 2.

[A4SoftWalker]

What is bad about flutter? I used to get it with my K04 and Forge 007 but I just thought that's how it sounded with a aftermarket TIP and intake. Didn't have any vacuum leaks and still held strong boost, 26 spike, 22 hold on Revo stg. 2.

Flutter on a piston type valve is a lot different than a diaphagm valve fluttering because it was installed the "wrong way". I might cause the R1 to "kick the bucket" and stop working. Which is what might be reason for the flutter in the 1st place - A RIPPED VALVE and also could lead to the decrease in boost pressure.

Just a few thoughts