Anyone had this fault?

[alexbradford]

17964 - Charge Pressure Control: Negative Deviation
P1556 - 35-00 -

^^^^ Anyone had this problem and actually manage to solve it? Think this could be my boost problem, Keeps puting the car into limp mode. Im not 100% but I think its only doing it when I put the foot down in 5th?

 

[PhilW]

Boost leak more like.

Log it and see whats going on.

 

[alexbradford]

Have Vag-com tried to do logs but no idea what to look for.

 

[Seatmann]

Check all the big boost pipes coming from the turbo to the intercooler and back up to the inlet manifold, any sign of an oily patch around any of the connections could be a leak, replace the vacuum pipes cause they're as cheap as anyway and make sure the actuator on the turbo isn't stuck.

 

[alexbradford]

Anybody any ideas on the this, Changed the N75 valve today and checked for boost leaks but cant find any. Car still only boosts to 10psi. Anybody with vag-com want to do some logs for ££.... Or if you know how to do logs I have Vag-com.

Forgot to mention, since clearing that fault its not came back up.

Its only happend since fitting the intercooler. But theres no leaks, everything is Tight! no holes in any pipes

 

[leighwinter]

I would also like to no this because my brothee has the exact same problem

 

[Seatmann]

You might need to pressure test the boost system by the sounds of it, there must be a leak somewhere, you could also try disconnecting the pipe to the actuator for the turbo and see if the boost goes up, if not then there's a leak or the wastegate's stuck open.

 

[alexbradford]

Wastegate, As in Dumpvalve, I noticed it was soundind different anyhow, If I disconnect the pipe from the actuator, will the boost not go up alot?

 

[Seatmann]

If it goes up to far the car will just go into limp mode, it's a self protection thing on the vag cars and you can reset it by restarting the car so it's safe to try. Wastegate as in wastegate, there's an actuator connected directly to the turbo with a rod that goes to the wastegate, pull the pipe for the actuator.

 

[leighwinter]

How do you do a boost leak test

 

[Seatmann]

Here's a link for the tdi's but the principles the same.

http://www.myturbodiesel.com/1000q/multi/boost-leak-tester-DIY-check.htm