125kw TDI Golf MkV BMN - Engine Speed Sensor (G28) and P3138 Intake Manifold Dev Errs

[benough]

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 have the identical car/engine, and his issue. The solenoid that pulls the flaps was filthy so I cleaned it. Unfortunately I forgot to put on bolt back in so it doesn't always move properly.

What I suggest is, if you are going to remove the EGR body and the shutdown flap, you should have enough access to clean the arm/rod that moves in and out to pivot/control the runner.

Do easy things first, as this rabbit hole can be hard to climb out of.

[Pete N]

Thanks Ben - thats interesting, and confirms a couple of things for me..

Spent a few hours trawling forums last night and it seems that the factory fitted BMN inlet manifold arm operates flaps in the vents, that at low speeds tumble the air to get better air/fuel mixing.

The flaps wear over time, due to a plastic seal not being protected from the heat (design flaw) and then oil starts to leak in/out the now floppy flaps.

The car smells of EGR type fumes when it starts (a strong smell, not normal diesel) and I have smatterings of oil coming from the O ring seal above the EGR, along with a fair bit of soot up in the chamber (I got a snappy with my phone by taking off the bottom pipe and shining a torch up there)

Its possible my EGR issues add to the DPF soot build up (my DPF gets to 40% every 4 days with very short journeys)

Anyhow, what I discovered is interesting.

It turns out that quite a few BMN engine owners (audi, skoda, golf and so on) have dumped the BMN plastic inlet and retrofitted a complete new alloy BKD inlet. This removes the flaps that cause the leakage issues, and gives the car a new lease on life, and runs smoother with no power difference.

I am mainly doing this because its 100 quid from the uk (plus 46 postage) instead of 425 quid for a factory plastic one, and is easy to fit.

Darkside in the UK even have a kit for it, being its a common issue.

https://www.darksidedevelopments.co....rsion-kit.html

I chatted with them and its only a 2 hour simple job, they provide all the gaskets and some shorter/longer screws as the alloy manifold is slightly different.

This will negate the need for that arm, flaps, and generally make it more robust. The only issue is the low air pressure turbulence will not be present, however people who have done this say it runs fine at low revs, and this is probably due to the inside of the alloy manifold being a rougher surface and pre turbulating (?) the air..

I was quoted 6-8 hours to fit the new manifold by a well known VW shop, and the cost of the manifold is about $1k so for $100 quid + postage I am going to be well happy.

Are you having issues with your DPF too? I have that pretty much worked out if you are.. I bought the VCDS and cable and chack it every few days and make sure I burn down he freeway in top gear 2k revs fro 10 minutes, and all good. DPF light hardly comes on any more.

The G28 sensor is also reportedly triggered by soot build up somehow so hopefully that will be fixed too!

This car is a pain in the a$$ mechanically, non common-rail and DPF are not very compatible, but I love driving it.. so its worth trying to get more life out of it.