EGT sensor (G235) failure

[muddyboots]

Just had this happen to me.

 

Driving home last night, got flashing glowplug light and warning message. Car still drove fine.

 

Scanned it with VCDS, got this:

 

                Address 01: Engine       Labels: 03L-906-018-CFF.clb
Control Module Part Number: 03L 906 018 BS    HW: 03L 906 018 BR
  Component and/or Version: R4 2,0L EDC   X23 7829
           Software Coding: 00190012042700080000
            Work Shop Code: WSC 00000 000 00000
              ASAM Dataset: EV_ECM20TDI01103L906018BS 003005 (SK35)
                       ROD: EV_ECM20TDI01103L906018BS_003.rod
                      VCID: 7CFC60C1F7E7ACA295-8028
1 Fault Found:
8669 - Sensor 1 for Exhaust Temp Bank 1 (G235) 
          P0544 00 [167] - Circuit Malfunction
          MIL ON - Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 2
                    Mileage: 133922 km
                    Date: 2067.14.17
                    Time: 07:42:32
                    Engine speed: 2520.50 /min
                    Normed load value: 56.5 %
                    Vehicle speed: 113 km/h ;)
                    Coolant temperature: 84 °C
                    Intake air temperature: 21 °C
                    Ambient air pressure: 980 mbar
                    Voltage terminal 30: 14.260 V
                    Unlearning counter according OBD: 40
                    Exhaust gas temperature sensor 1: 20.0 °C
                    Exhaust gas temperature sensor 2: -0.0 °C
                    Exhaust gas temperature sensor 3: 241.9 °C
                    Exhaust gas temperature sensor 4: 196.4 °C
                    Shut-off timer: last engine shut-off time: 31414 s

Readiness: N/A

This morning it started doing a regen, and was quite lumpy, so hooked up the laptop and did some logging.

EGT Sensor 1 (which I think is in the exhaust manifold) was fluctuating randomly from around 0-300degC, when it should normally be upwards of 550degC during a regen (the downstream sensors were reporting well over 400degC).

I was also getting grey smoke during acceleration, which presumably is unburnt diesel due to the ECU overfuelling as it doesn't think the EGT is high enough.

The DPF soot loading wasn't reducing anywhere near as quick as it should either - I guess the overfuelling is adding soot to the DPF as quick as it's burning it off....

 

Over the last few months, I've been getting grey smoke under acceleration during the last few minutes of each regen (but no other time) - so it's possibly been failing for a while, just not enough to flag a fault.

Hopefully this will fix it.

 

Car is booked into an independent specialist on Friday - fingers crossed it won't cost a kidney!

 

 

Edited 8 March, 2017 by muddyboots

[Sad555]

have you had the fix

[muddyboots]

The emissions fix ? No.

 

Googling suggests failure of this sensor isn't uncommon across VAG TDIs.

[Ryeman]

Fingers crossed 

[muddyboots]

All sorted now.

New sensor itself was around £130+VAT, plus labour (less than an hour).

It's the one in the exhaust manifold, tucked under the turbo, so a little tricky to get to.

Didn't drive it much between the fault occurring and getting it fixed - as I suspect the car won't perform any regens while this sensor is faulty; in which case if the soot loading became excessive, I'd have had far more trouble with a blocked DPF....

[Ryeman]

1 minute ago, muddyboots said:

All sorted now.

New sensor itself was around £130+VAT, plus labour (less than an hour).

It's the one in the exhaust manifold, tucked under the turbo, so a little tricky to get to.

Didn't drive it much between the fault occurring and getting it fixed - as I suspect the car won't perform any regens while this sensor is faulty; in which case if the soot loading became excessive, I'd have had far more trouble with a blocked DPF....

Must be a relief for it to be only a sensor failure and so easily fixed.

[TDISuperb09]

I have the same error come up sporadically with my 09 TDI superb. Which color connector was it?

 

i checked mine and there are 3 different colours so want to be sure before I go changing it.