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Discussion Starter #1
Got chipped on thursday and i took the wagon out for a bit of a drive today... after driving it hard for a bit it would lugg once it hit boost. Is this limp mode... vacume leak??? Any help is greatly appreciated
 

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Engine code? (AEB/ATW/AUG/AWM)

Are you using the stock diverter valve?

Which chip? Did they recommend changing to different spark plugs or a different FPR? Did you install them?

What octane gas are you running?

I don't think you're "limping" -- if limp mode is triggered by overboosting, it stays on until you turn the car off and restart it.
 

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Discussion Starter #3
It is an ATW motor

Stock DV with a Forge 007 comming friday

I am running REVO and wasnt notified of diff. spark plugs or FPR.. i would imagine a 4bar is fine though.

I run 91oct on a 91oct program

And it ran just fine for the first couple of days and then acted up the other night after some spirited driving.
 

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I'm betting it's the DV... a few days of "boosted" driving wore it out.

Get that forge installed! :thumbup:
 

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Discussion Starter #6
Well i installed the Forge valve with the 15-23psi spring and its still doing the same thing. When i give it full throttle and right about when it hits 18psi the needle kinda shakes and it luggs a couple times. Any other ideas what it would be??
 

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Discussion Starter #11
Dirty Dan said:
let us know if that works for ya, i was having a simmilar problem and that fixed it
Will do.. im gonna do it in the morning... i hope it fixes the problem. I cant even give it a good amount of throttle without it kicking a few times.:thumbdown
 

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I'm wondering if the fueling is going slightly too lean under open-loop at WOT, causing some knock retard to kick in...

Try some 93 octane gas if it's available in your area. Check the same thing: WOT pulls and 3/4 Throttle pulls in both 2nd and 3rd. (91 seems like it might be a little bit low for 18psi (~1.25 Bar) ). Upping the octane will require less knock retard, if the fueling is *almost* okay. If the fueling is way lean, you'll need to make more fueling adjustments.

See if there is a specific boost pressure, below which everything is okay: try feathering the throttle to keep the boost at 16psi, 15psi, etc.

We need more data...

Anyone with a VAG-COM near you?
www.frappr.com/vagcomlocator
http://www.steve-hall.com/cgi-bin/VAG-Locator.pl
 

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Discussion Starter #14 (Edited)
I just did a couple pulls, feathering to about 15psi when it would spike and then easing into full throttle about 4kRPM where its about 16psi. It does not do the same thing, it only does it at WOT around 3kRPM when i hit that 18-20psi spike. Next time i fill up i will get a full tank of 93 and see if that helps any.

pete1 said:
I'm wondering if the fueling is going slightly too lean under open-loop at WOT, causing some knock retard to kick in...

Try some 93 octane gas if it's available in your area. Check the same thing: WOT pulls and 3/4 Throttle pulls in both 2nd and 3rd. (91 seems like it might be a little bit low for 18psi (~1.25 Bar) ). Upping the octane will require less knock retard, if the fueling is *almost* okay. If the fueling is way lean, you'll need to make more fueling adjustments.

See if there is a specific boost pressure, below which everything is okay: try feathering the throttle to keep the boost at 16psi, 15psi, etc.

We need more data...

Anyone with a VAG-COM near you?
www.frappr.com/vagcomlocator
http://www.steve-hall.com/cgi-bin/VAG-Locator.pl
:poke:
 

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Discussion Starter #15
Well took the throttle body out, and it was super clean. That makes me happy concidering the car has 75k miles on it. But anyway i cleaned it up a bit since it was out anyways. Noticed no difference. Ill keep you updated on the VAG-COM and the 93 oct.

And a picture from the test drive :)
 

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i jus started to have the same problem
when i hit 15+ boost feels like its slipping away somewere but no power
i jus did a test pipe mod
my thaughts: Clutch, breather hoses, down pipe gasket busted, car feels almot unchipped
 

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Discussion Starter #17
Turbox said:
i jus started to have the same problem
when i hit 15+ boost feels like its slipping away somewere but no power
i jus did a test pipe mod
my thaughts: Clutch, breather hoses, down pipe gasket busted, car feels almot unchipped
See with mine its a pretty violent kick 2 or 3 times until the boost drops to around 15psi. I just wonder why it drove fine right after my flash for about a week and then started acting up.
 

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My hunch is still fuel trims -- it took a few days of driving for the trims to reach a point where the WOT (open-loop) fueling map is now causing a slightly lean condition. Lean A:F at WOT & high pressure at WOT --> more heat --> greater chance of knock/predetonation --> knock sensors notice incipient knock --> radical timing retard --> lugging.

...of course all this is a GUESS, until we can look at some fuel trim, timing, A:F, and knock sensor data....
 

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Discussion Starter #19
pete1 said:
My hunch is still fuel trims -- it took a few days of driving for the trims to reach a point where the WOT (open-loop) fueling map is now causing a slightly lean condition. Lean A:F at WOT & high pressure at WOT --> more heat --> greater chance of knock/predetonation --> knock sensors notice incipient knock --> radical timing retard --> lugging.

...of course all this is a GUESS, until we can look at some fuel trim, timing, A:F, and knock sensor data....

While i still have some 91oct left i will head to my buddies shop with the VAG-COM tomorrow to check full trims. If it looks lean then i will fill up with 93 and check them again. Also.. any thought that it could be the N249?
 

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I suppose it could be the N249, if it was only slightly malfunctioning. The N249 is the solenoid valve that lets vacuum through to the DV. The N249 is located under the manifold, approx. under the intake runner for cylinder 2.

Bentley suggests checking the resistance across the N249's two pins (with the harness unplugged). Resistance should be 25 to 35 Ohms.

You could also try hooking the DV vac line directly to the intake manifold, bypassing the N249 completely.
 
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