Boost Pressure Control Valve?

[BoSNiaN]

Just checked my car for codes and found this:

1 Fault Found:
008801 - Boost Pressure Control Valve (N249): Mechanical Malfunction
P2261 - 000

Anyone know where this valve is or what it does? Ross-Tech only says THIS about it....Its especially weird because it happens once every few hundred KM's apparently but doesn't actually trigger a check engine light

[Jay-Bee]

Really?

It's like the second most commonly failed part on the 2.0T

Diverter Valve

[BoSNiaN]

Whaaat?! Did not realize Diverter Valve = n249

[CorneliusRox]

no, I am 99.99% sure n249 is your wastegate valve. It is on your turbo, has the same connector as the DV (so dont mix them up on accident), and is in line with the tube from charge air to the wastegate to help control it better.

[BoSNiaN]

no, I am 99.99% sure n249 is your wastegate valve. It is on your turbo, has the same connector as the DV (so dont mix them up on accident), and is in line with the tube from charge air to the wastegate to help control it better.

Thanks for this, and yah, looks like you were wrong Jay-Bee

Seems also to be known as the N75 valve and here's what it looks like in ETKA (#2):



Part # 06F906283F shows this on ECS:

[CorneliusRox]

Might as well get an in line MBC while you're at it. Just get one more tube and put it in line after the N75 and before the wastegate.

[Jay-Bee]

I'll blame it on posting at 2:50am after I was woke up for a stupid bunked service call at my workplace.

lol

And the N249 works differently on 1.8T

[DoThisMyWay]

I got that same code and have the new part in hand but like the OP stated, the code is a soft error and random. I might just replace it anyway.

[BoSNiaN]

I got that same code and have the new part in hand but like the OP stated, the code is a soft error and random. I might just replace it anyway.

How much was it and where'd you get it from? Did you have any issues or you found the code randomly? I actually don't feel like I have any issues with the car so I might not even replace it...If anything, I get boost really early on (1st and 2nd gears even) and it holds so Only thing I am worried about is it damaging my diverter valve or even turbo if it is broken...

[jmarch1122]

You don't need to worry about damaging the DV, but if you have an aftermarket one, like a forge, then using a spring that is too stiff can harm the turbo itself. I am still trying to find a scientific explanation of how to choose the right spring and/or spacers to match your application.

[DoThisMyWay]

It cost 40 something from GAP. I was experiencing turbo flutter when I let off the gas. It turned out to be my Rev C DV was broken inside and fluttering when the DV piston was retracted. So, I don't really know if the DV caused the code for the boost pressure control valve or its really faulty or broke because of the DV. I do notice when I get on it in 2nd, I get a stutter like boost isn't really holding like it should. I just replaced the plugs and cleaned up the coils, so I'm pretty positive it's not a soft misfire. Other than that, boost feels strong in all the other gears and speeds.

[CorneliusRox]

chatter is caused by the DV not working properly. getting rid of it is the DV's only task. And this saves life on a turbo. I have seen shafts snap on vehicles without a DV or BOV when they are on it hard and let off right away.

the N75 works in like with the wastegate. The wastegate has a spring in it and a diaphragm and the pressure from the charged air pushed on that and reroutes exhaust air so it doesnt hit the turbine (basically bleeding energy/boost). The N75 is in line of that an controls the air sent to the wastegate. I am pretty sure that our cars are setup with 'boost by gear' which will limit the boost on the lower end and in the higher gears it lets it go more.

If you throw a manual boost controller on, you can control it with the tune, and also by hand. You can let the N75 limit your boost so you get a smooth ride, but you also can limit what the N75 can do so you get more boost.