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Discussion Starter · #1 ·
I'm having some issues with my new DV after upgrading to the REVO stage II.

We started to go off on a tangent in another thread, but I wanted to hear from other owners of this DV if anyone else is having an issue.

During hard acceleration, between shifts (usually 4th to 5th), I hear a fluttering sound (hence, a VAG queef ;D), the engine momentarily looses power for about 2-3 seconds, you coast for those two to three seconds and then power is restored. In one incident, while trying to pass a big rig and stomped on it, only to have to tuck in back behind him.

Environmental: 85F or greater, low humidity

Engine setup: Neuspeed: CAI, turbo discharge kit, and exhaust and Forge FMFSITV

Mr. 22350 is having similar issues, but is running different engine management software. I've spoke to the folks at Forge and I'm going to do some data logging and see if I can re-create the issue whilst logging.

My guess is possibly too much boost and I have yet to use my Revo SPS/Select to tweak any settings on the ECU.
 

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Discussion Starter · #3 ·
manricky said:
thats really weird man.
Yeah... I know. Sucks becuase I was gonna try to road race next week :'(

If it's not dialed- there's no use. I can't say it's one vendors fault over another, nor am I trying to blame them- and it is a "who-dunnit". :-\

Racing improves the breed and I'm finding out the hard way. ;)
 

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Discussion Starter · #7 ·
GTfly said:
i bet it was yer DSG then. mine does the same also occasionally if im running it hard for a long time.
How did you determine it was your DSG?
 

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Just because it does it when you shift gears doesn't mean it's coming from the transmission. Gearshifts also happen to be a big part of the DV's job. Now the fact that it stopped when you got the dog bone mount might mean something. I don't know what, but it could be significant in figuring this out.
 

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WELL I DIDNT SAY IT STOPPED BUT I RARELY EVER DOES IT NOW... I CANT EVEN REMEMBER THE LAST TIME IT DID IT... BUT CONSIDERING THAT I CANT REMEMBER IT DOING IT SINCE I HAVE THE HKS SSQV EITHER... HAH GUESS WE ARE BACK TO SQUARE ONE.
 

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I think someone already said this, but it REALLY sounds like the DV isn't opening fast enough and you're getting backpressure. The higher gears is where the engine is put under the most stress, so it may be affecting it all the way through, but you only notice it the most in 4th-5th. Are you getting that sound from the turbo when air starts flowing up over top the blades (like a water pump that's not primed)? Do you have any vacuum leaks?
 

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Discussion Starter · #15 ·
Here's the latest update:

I downgraded :( back to Stage I... no issues so far.

Before the downgrade, they dumped the ECU codes and I had "low fuel pressure" codes but no CEL.

The low fuel pressure would explain the loss of power.

They guys from Genesis Engineering sent me this (which I assume is from GIAC) and a few APR Stage II folks are having the same issue:

"The guys at Genesis Engineering just sent me this: (not sure who the source is but my guess is GIAC)
"Special Note Regarding Fuel Pumps on the 2.0T: There is some debate regarding the performance effects of the high pressure fuel pump, found in the engine bay and required to produce the extremely high fuel pressures of the FSI system. The factory has superseded the high pressure pump part number from 06F127025B to 06F127025F. There is no definite cutoff date when cars began coming equipped with the 06F127025F part number, and the only real way to tell which pump your car has is to remove the engine covers and look at the part number on top of the high pressure pump. On the B7 chassis A4, the pump is located near the firewall at the end of the fuel rail as in the below picture. On all other 2.0T cars, it is found at the end of the fuel rail towards the driver side front of the car.
If your vehicle is equipped with the old part number pump 06F127025B, we recommend using the Sport Flashloader chip program available for your vehicle to prevent surging issues, especially if you have an aftermarket high flow cat and exhaust system. GIAC has done extensive testing on multiple 2.0T vehicles and has found a correlation between surging with higher boost levels with the old pump number. If your vehicle is equipped with the new part number pump 06F127025F, you can opt for the X-Chip Flashloader file if available.
If your vehicle is equipped with the old part number pump, there are very limited new part number pumps available for purchase at this time. There is also the possibility of getting the new pump installed under warranty free of charge. Contact your VW/Audi dealer for more information."
 

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Discussion Starter · #17 ·
GTfly said:
could also be yer PCV valve... you get it blocked off or order a new upgraded one of them?
I plan on doing the PCV w/ the check valve and the fuel pump before I go back up to stage 2.
 

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I checked my PCV as well. Sure enough there was a bit of oil around the fill cap/seal. I almost spent $140 on the new OEM PCV when I saw that. Unfortunately, my car already has the updated PCV. I am going to try and get a dealer to replace it under warranty. FYI, oil being blown back out of the cap is an easy way to see if your PCV is failing. The back pressure has to go some where and the cap is the weakest and easiest place for it to leak.
 
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