Loss in power

[brad65ford]

Well I'm hopeing someone has had a similar problem and knows the answer. I've had my A4 2.0 06 for a year now and has been flashed stage 1 since 200 miles I now have 6000 miles. I though I bought some bad gas so I refilled up with new super from somewhere else and no luck. The only things I can say is the turbo isn't making a drill noise, and I'm now not getting the air sucking sound anymore like I used to when I changed over having the flash done. Is it possible to have a flash go away after all this time? I haven't unpluged the battery yet don't know if that would do anything. And I check all visual things under the hood? Any help would be greatly appreciated.

[Quattro4mage]

You need to check for codes with VAG-COM, but it may just be a torn diverter valve. I have never had a problem with mine but I am not flashed. They seem to be prone to fail even on stock 2.0Ts.

[b7cruiser]

You might want to check the screen on the intake (it's before the air filter) for debris. When I took it off (for schitz and giggles), I noticed that there was a lot of small leaves and crap, sucked in from the front of the car.

[brad65ford]

You might want to check the screen on the intake (it's before the air filter) for debris. When I took it off (for schitz and giggles), I noticed that there was a lot of small leaves and crap, sucked in from the front of the car.

I checked it and it had very little stuff i it.

Quattro4mage, where is this valve so I can remove it and inspect it.

[fast_audi]

coilpacks failure would be my guess. use a vag-com to identify the problem

[brad65ford]

wouldn't I fell a coilpack though, I remember my b6s4 coilpack when one when't it shook the car. It runs smooth you get some boost right away but the power just seems to fade

[mrponline]

Where is this valve so I can remove it and inspect it.

Located on the turbo (see pic below). In order to get to it you will need to remove the plastic tray beneath the car.

But i would suggest using a VAG COM to diagnose the problem first.

[brad65ford]

how will the VAG COM show me anything it I don't have any check engine light?

[PRESSURIZEDB7]

I wonder if you've gone into limp mode. could be a sudden fuel pressure problem. vag the car.

[brad65ford]

anybody with a VAG COM in the northern jersey area.

[mksap11]

how will the VAG COM show me anything it I don't have any check engine light?

Not all faults will cause a CEL, though a boost leak should. Best bet would be to check for codes in the engine block (01) with a CAN capable cable.

I recently experience similar power loss in my car. The fault code that was generated combined with a data logging of the requested vs. actual boost confirmed a boost leak. $45 for a new DV and an hour of my time to install it is all it took.

There's actually a TSB from Audi regarding bad/faulty DV valves (called "Turbocharger Recirculation Valve N249 in the TSB)

[parks853]

Not all faults will cause a CEL, though a boost leak <i>should</i>. Best bet would be to check for codes in the engine block (01) with a CAN capable cable.

I recently experience similar power loss in my car. The fault code that was generated combined with a data logging of the requested vs. actual boost confirmed a boost leak. $45 for a new DV and an hour of my time to install it is all it took.

There's actually a TSB from Audi regarding bad/faulty DV valves (called "Turbocharger Recirculation Valve N249 in the TSB)

everyone is correct. Scan the car with vag-com.

[brad65ford]

OK I'm back from Dynamic Motorsports in Warwick NY, they were are the ones that flashed my car last year with Revo stage one. And guess what no codes! The Revo flash is still in the car, but the boost is half what it should be. They don't know if its the tubro or the DV. Joy I hate to throw money into installing and purchasing a DV but what am I gonna say at the dealership, "Well its as fast a stock but I'm not make the boost I want with a chip, change the tubro" LOL that would be funny. Anyway any help would be greatly appreciated. Thanks Brad

[mksap11]

A failed DV is becoming a fairly common cause of not making boost. Bad PCV valves on the transverse 2.0Ts have also been culprits. I supposed you could have a bad turbo, but DVs are about $45 and PCV valves (with all hoses) about $150...both far less than a replacement turbo.

Anyway, I'm assuming that they logged engine block 115 that showed that your actual boost was lagging far behind requested?

Determining if your DV has failed is as simple as:
1) put car on ramps (or lift if you've got one)
2) remove belly pan
3) remove DV and inspect

If it has failed, it'll look something like this:



If you go through the trouble of doing steps 1-3 and find that yours has failed, you might as well just replace it yourself... just my $.02

[brad65ford]

Thanks bro, do I need special tools for this?

[mksap11]

No, not really provided that your tool box is decently well equipped and that you have ramps or access to a lift. The belly pans come off with a flat head screw driver and the DV is held into place by 5 or 6mm hex bolts. (I used a Torx T-25). The only complicated aspect is that the confines are pretty tight. If you have a small 1/4" ratchet with extensions, you should be all set.

[brad65ford]

Just want to follow up and let you guys know its fixed. My orginal Bypass Valve looks like the one it the picture above. It runs great again. Hope this help people out in the future when this happens to them.
P.S. is it worth the money for a drop in K&N or just leave it alone.

[Re5pectThe_Cuz]

sorry to revive this thread but I seem to have a similar problem. Did you have horrible gas mileage as well? Im losing 1/2 a tank in a days drive. This consisted of 20 miles each way. Going and coming back from the dealer, which of course said, "could not replicate"
the car is still slower than stock. It doesnt even move and I hear a hissing noise

[djs]

K&N not worth it in my opinion; might mess with your MAFS too.

[Re5pectThe_Cuz]

sorry to revive this thread but I seem to have a similar problem. Did you have horrible gas mileage as well? Im losing 1/2 a tank in a days drive. This consisted of 20 miles each way. Going and coming back from the dealer, which of course said, "could not replicate"
the car is still slower than stock. It doesnt even move and I hear a hissing noise

anny help?

[4-tified]

OK I'm back from Dynamic Motorsports in Warwick NY, they were are the ones that flashed my car last year with Revo stage one. And guess what no codes! The Revo flash is still in the car, but the boost is half what it should be. They don't know if its the tubro or the DV. Joy I hate to throw money into installing and purchasing a DV but what am I gonna say at the dealership, "Well its as fast a stock but I'm not make the boost I want with a chip, change the tubro" LOL that would be funny. Anyway any help would be greatly appreciated. Thanks Brad

So, with the boost leak you think your A4 is as fast as stock still?

I'm wondering if the DV ripping is a general problem in the newer B7's stock, or does it happen mainly with "chipped" engines, or maybe it's both and the stock piece really sucks that bad?
I've noticed a slight decrease in what I think my A4 should be putting out as well.
Also, the once smooth power curve seems to be a bit "choppy/notchy".
The power feels like it comes on, then goes flat, then comes on, flat, etc...
This happens pretty fast, but I can feel it just barely.

My A4 is stock, so it can't be the added boost pressure of ECU mods.

Also, has anyone heard of this happening on the 2.0T FSI in the A3 and GTI/GLI?
Is it that same part number?

[mksap11]

It's a general problem. Audi issued a TSB regarding failed DVs back in December and also revised the part.

[mksap11]

sorry to revive this thread but I seem to have a similar problem. Did you have horrible gas mileage as well? Im losing 1/2 a tank in a days drive. This consisted of 20 miles each way. Going and coming back from the dealer, which of course said, "could not replicate"
the car is still slower than stock. It doesnt even move and I hear a hissing noise

If you have a vag-com, you can log block 115 that measures requested and actual boost. If your actual boost always significantly lags behind requested, you have a boost leak. The most common causes of boost leaks in the 2.0T FSI motor seem to be faulty PCV valve and torn recirculating valve (DV) gasket.

[Re5pectThe_Cuz]

i took it to the dealer and bastards said its perfectly fine... iknow itsnot!

[B7AudiA4]

Having the same issue. Blown coilpack?