p0299

[cutchie]

So I've had the underboost fault for a wile now replaced the dv pcv and the waste gate actuator, this week I fitted a boost gauge and got the car smoke tested. I'm getting 4 psi and dropping to 3/3.5 and no boost leaks were found anyone any ideas where to go from here?

[cutchie]

Sorry waste gate solenoid**

[Ricky123]

Any mods?
Have you had a scan done with vagcom?

I'd double check all pipes, check intercooler for cracks too.

[Dan648v]

Had this code on my gfs a3 tdi and it was the actual actuator at fault. Replaced the unit and boom. Boosting again! Think the diaphragm had split inside?

[Dan_FR]

So you've replaced the N75 rather than the actuator? Does sound like the actuator is at fault, not unheard of as mentioned above

[Dan648v]

Take it to a garage and get them to vacuum test the actuator. That'll tell if it's working, that's what my Audi tech did 

[cutchie]

So thought I would update this I've now replaced the turbo and the fault is Still the same still peaking at 4psi every time anyone any other ideas?

[Dan_FR]

4 psi is about actuator pressure when measured at the inlet

Data logging with VCDS is needed need to check all readings and whether the ECU is requesting boost (N75DC% - block 116 from memory - or thereabouts)

[cutchie]

003



114



115

[cutchie]

these are the graphs I logged but tbh I don't really know what im looking at or for! lol does anyone else see out anything out of place?

[Dan_FR]

Can you share a link to the CSV files? Are they full throttle runs?

[cutchie]

114
https://docs.google.com/spreadsheets/d/1PTMxiKdea3u4Hk5xOhv54VMDXFdbhSrqKX--NskzNMQ/edit?usp=sharing

115
https://docs.google.com/spreadsheets/d/10l493f3-sEKsM9ZqXpVOucRNd7IjW9-yjBkonb2qLT8/edit?usp=sharing

003
https://docs.google.com/spreadsheets/d/11ASpZUR1Wx3SEpepYzUAtV2AzLGFrtiGMIUAI2hVTuU/edit?usp=sharing

yes all third gear pulls to around 5750 ish
cheers mate

[Dan_FR]

Not really helpful as those logs were done separately.

Log these blocks:
114 115 118
001 002 003
031 023 231
091 118 003

So log 3 at a time on each run (press the turbo button), and do a single full throttle run in 4th gear from 2k rpm to as high as possible. Only log this - no other data

Someone else having the same issue on the FB Page TFSI Tuning:
https://www.facebook.com/groups/529405700525327/permalink/723181707814391/