So the coil light started flashing today on my Golf Mk5 2.0 TDI (125kw) 2008 with BMN engine.

I got the following from VCDS:

2 Faults Found:
000801 - Engine Speed Sensor (G2 <--- This has been happening for a while with no coil light
P0321 - 006 - Implausible Signal - Intermittent
Freeze Frame:
Fault Status: 00000001
Fault Priority: 5
Fault Frequency: 7
Reset counter: 37
Mileage: 148272 km
Time Indication: 0
Date: 2000.00.00
Time: 07:05:53

Freeze Frame:
RPM: 160 /min
Torque: 0.0 Nm
Speed: 0.0 km/h
Time: 0.01 s
Angle: 0.0 °
Bin. Bits: 00000000
Bin. Bits: 00000001

012600 - Intake Manifold Runner Control <--- This is new...
P3138 - 006 - Regulation Deviation
Freeze Frame:
Fault Status: 11000001
Fault Priority: 5
Fault Frequency: 2
Reset counter: 40
Mileage: 148332 km
Time Indication: 0
Date: 2000.00.00
Time: 08:51:41

Freeze Frame:
RPM: 2560 /min
Torque: 0.0 Nm
Speed: 73.0 km/h
Mass Air / Rev.: 468.7 mg/str
Mass Air / Rev.: 588.6 mg/str
Lambda: -20.3 %
Text: Kein Messwert verfuegbar

I have looked up the Intake Manifold Runner Control issue and it looks like a replace of the manifold might be in order, Unless a clean will fix it. Maybe a sticky valve ?

Can anyone suggest what I should look for to help diagnose this issue - My EGR needs a good clean, and the car goes pretty well most of the time, although often when in idle, it can get real lumpy for no reason - intermittently..

I had a lot of problems with DPF and have them under control now. Cost me a couple of grand to get there though. Wish I had bought VCDS before getting into a limp mode situation !

Thanks!