2015 Q5 TDI - would not go past 90km, glow plug light came on- has codes PO401 and 403

A1sailor

Well-known member
Joined
Apr 15, 2018
Location
Ontario, Canada
TDI
2015 Q5 TDI 3.0
What should I do?
I'm driving on the highway at 100-110km for an hour, glow plug light comes on, tried to accelerate but vehicle would not speed up, I could hold speed at 90km range but just barely, this lasted about 30 minutes. Made a stop, shut down for 30 minutes and all ok after that, happened 30 days ago.
Ran a scan yesterday and got PO401 & 403.
Vehicle still under dieselgate warranty for another 10,000 km. Problem has not happened since?
I can post full scan but for now here are fault codes;

4 Faults Found:
4807 - EGR System
P0401 00 [00100000] - Insufficient Flow
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Priority: 2
Fault Frequency: 1
Mileage: 182834 km

Date: 2024.05.23
Time: 13:16:21
Engine RPM: 699.50 /min
Normed load value: 34.9 %
Vehicle speed: 0 km/h
Coolant temperature: 92 °C
Intake air temperature: 29 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.280 V
Unlearning counter according OBD: 25
Mean injection quantity: 10.42 mg/stroke
Control Module temperature: 61.3 °C
EGR_governor_deviation: -157.1 mg/stroke
Inj Ctl q Curr: 10.42 mg/stroke
Standardized air flow ratio: 1.1053
Air mass at air mass meter 1: 50.3 kg/h
Actual charge pressure: 1042 hPa

9120 - EGR Sensor 1
P046C 00 [01100000] - Implausible Signal
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Priority: 2
Fault Frequency: 1
Mileage: 182825 km
Date: 2024.05.23
Time: 13:10:38
Engine RPM: 1326.00 /min
Normed load value: 99.6 %
Vehicle speed: 88 km/h
Coolant temperature: 89 °C
Intake air temperature: 28 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.300 V
Unlearning counter according OBD: 25
Air mass: actual value (mg/stroke): 346.4 mg/stroke
EGR Vacuum Regulator Solen.val.: activation: 100.00 %
EGR Solen.val.: actual value: 94.73 %
EGR valve: offset closed: -3.38 %
High press EGR actuator: actual unconditioned volt val: 1094.8 mV
EGR valve: offset open: 3.38 %

31982 - EGR Valve (N18)
P0403 00 [00100000] - Malfunction
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Priority: 2
Fault Frequency: 1
Mileage: 183344 km
Date: 2024.05.30
Time: 10:57:22
Engine RPM: 1334.50 /min
Normed load value: 23.9 %
Vehicle speed: 88 km/h
Coolant temperature: 89 °C
Intake air temperature: 21 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.160 V
Unlearning counter according OBD: 32
Air mass: actual value (mg/stroke): 240.6 mg/stroke
EGR Vacuum Regulator Solen.val.: activation: 100.00 %
EGR Solen.val.: actual value: 94.12 %
EGR valve: offset closed: -3.63 %
High press EGR actuator: actual unconditioned volt val: 1124.0 mV
EGR valve: offset open: 3.63 %

31983 - EGR Valve (N18)
P0403 00 [00100000] - Malfunction
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Priority: 2
Fault Frequency: 1
Mileage: 183344 km
Date: 2024.05.30
Time: 10:57:21
Engine RPM: 1337.00 /min
Normed load value: 16.5 %
Vehicle speed: 88 km/h
Coolant temperature: 89 °C
Intake air temperature: 21 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.180 V
Unlearning counter according OBD: 32
Air mass: actual value (mg/stroke): 260.9 mg/stroke
EGR Vacuum Regulator Solen.val.: activation: 78.33 %
EGR Solen.val.: actual value: 71.45 %
EGR valve: offset closed: -3.63 %
High press EGR actuator: actual unconditioned volt val: 1896.2 mV
EGR valve: offset open: 3.63 %
 

TurboABA

Top Post Dawg
Joined
Jul 24, 2010
Location
Kitchener, ON
TDI
RIP-2010 Jetta 6spd 2014 Touareg Execline '14 A6 Technik S-line
First and foremost, why aren't you taking it in if you have ANY codes and are still under warranty?
You won't like it when you have to pay for any of this on your own.

All the codes that you are showing are intermittent, so whatever took place a month ago, has long cleared by now.
It's hard to know with that kind of a gap in "data" what it could've been.... what are you DPF stats like?
 

A1sailor

Well-known member
Joined
Apr 15, 2018
Location
Ontario, Canada
TDI
2015 Q5 TDI 3.0
Thanks Turbo, due to travel could not get to dealer. Talked to them they said likely went into limp mode but they did not know why. They said if it happens again to bring vehicle in.
They asked not to clear any codes, I did not.
Had new DPF under extended warranty a few months ago, old DPF was ok, a sensor was relocated on the DPF which was the reason for the recall and DPF replacement. I have the DPF stats will post next week.
 
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