Anyone ever see this? 16683 - Can't Decode, CODE File Not Loaded! P0299 - 000 - - Intermittent

[gtrosema]

Monday,07,June,2021,09:00:30:39744
VCDS Version: Release 21.3.0 (x64) Running on Windows 10 x64
www.Ross-Tech.com

Address 01: Engine Labels: 038-906-016-BHW.lbl
Control Module Part Number: 038 997 016 N HW: 028 101 198 2
Component and/or Version: R4 2,0L EDC G000AG 1388
Software Coding: 0150034
Work Shop Code: WSC 05100 444 59153
VCID: 295E26E6836262C3B4-5000
1 Fault Found

16683 - Can't Decode, CODE File Not Loaded!
P0299 - 000 - - Intermittent
Freeze Frame
RPM: 2037 /min
Torque: 208.0 Nm
Speed: 108.0 km/h
Load: 45.9 %
Voltage: 13.91 V
Bin. Bits: 00101000
Absolute Pres.: 2050.2 mbar
Absolute Pres.: 1611.6 mbar


Readiness: 1 1 0 0 0

 

[Mozambiquer]

That's the infamous p0299 code. Low boost pressure. There's a lot on that code, if you search it, most commonly it's a split boost hose, stuck egr valve, failed camshaft or vacuum lines/pump sometimes it's a n75 valve, and very seldom it's a turbocharger.

 

[zzdiesel]

How do you diagnose a failing n75? Can it sause an underboost code and a MAF code?

 

[Mozambiquer]

How do you diagnose a failing n75? Can it sause an underboost code and a MAF code?

I'm sure there's a specific way to test it, but I check the continuity on the two terminals on the n75, though if there isn't continuity, it'll throw a code for the n75 itself.
Then I check vacuum and the turbo actuator, as well as all the lines. Only if those are all good, and the camshaft is good, and no boost leaks will I replace the n75 for a low boost issue.

 

[Scubanero]

Almost everything throws a MAF code and the cause is usually something else. I wish I had a nickel for every MAF sensor that got replaced and didn't fix anything.

 

[Mozambiquer]

Almost everything throws a MAF code and the cause is usually something else. I wish I had a nickel for every MAF sensor that got replaced and didn't fix anything.

Same here!

 

[jmh61255]

My 2004 Jetta BEW diesel also had an intermittent loss of boost condition (once every few days) that eventually progressed to continuous loss of boost and then tripping P0299. With a vacuum gauge connected between the wastegate bypass regulator valve (N75) and the VNT actuator first, and then the vacuum reservoir second while operating under driving conditions, there was zero vacuum in either line. However, when connecting the gauge ahead of the vacuum check valve there was sufficient vacuum indicating blockage occurring at the check valve. After reversing the check valve and retesting, vacuum returned as did the boost . Noting the check valve was installed correctly per the color coding (black to the vac source, white to the N18, N75, and vac reservoir) it seems the check valve failed and will be replaced. A week ago the MAF was replaced and immediately threw the P0101 CEL. I'll give the MAF a few days to assimilate now that the P0299 issue has been resolved. If the CEL persists I'll reinstall the original.