I am coming here to see if I can get help from my cousins/brothers/sisters.
Troubleshooting my wife's 2015 Audi q7 TDI. Has a "Stage 1.5" Malone tune since we bought it in late 2018. I got Yrtreg's TCM flash when he came up to Toronto, Canada many moons ago.
Had intermittent check engine lights for the past few yrs. Usually NOX sensor 2 intermittent/implausible signals. Last night she got a 350km to no restart warning. 1st time this has happened.
I just recently successfully replaced an Adblue transfer pump which pumps adblue up from the reservoir tank to the main tank. (Twice it was giving 1500km to empty warnings , and when I would go fill up the tank, it would only take 1-2 gallons (it's about a 5+ gallon system) Anyways new pump is in and working. Not sure if Toureg's have 2 tanks for adblue or not.
Apparently the 350km to no restart means that there is something wrong with the Adblue system. The q7's PCM is a little confused. It said something about Sensor 1 not being plausible.
is there any way that Nox 2 can be higher than the pre cat Nox1? I still think I have a problem with Nox2, and have ordered a cheap aftermarket one from Amazon. Reviewing the logging, sometimes my NOX2 sensor gives readings that are higher than NOX1; sometimes it's zero, a couple times I saw -100 ppm logged.
I cleared the 350km warning by clearing the engine codes.
I graphed the log file in Openoffice... Blue is the Nox1, red is Nox 2.... Took it on a 5 minute testdrive.
Troubleshooting my wife's 2015 Audi q7 TDI. Has a "Stage 1.5" Malone tune since we bought it in late 2018. I got Yrtreg's TCM flash when he came up to Toronto, Canada many moons ago.
Had intermittent check engine lights for the past few yrs. Usually NOX sensor 2 intermittent/implausible signals. Last night she got a 350km to no restart warning. 1st time this has happened.
I just recently successfully replaced an Adblue transfer pump which pumps adblue up from the reservoir tank to the main tank. (Twice it was giving 1500km to empty warnings , and when I would go fill up the tank, it would only take 1-2 gallons (it's about a 5+ gallon system) Anyways new pump is in and working. Not sure if Toureg's have 2 tanks for adblue or not.
Apparently the 350km to no restart means that there is something wrong with the Adblue system. The q7's PCM is a little confused. It said something about Sensor 1 not being plausible.
previously, it was always a sensor 2 failure... (I have not replaced the sensor, as it never affected driveability)18728 - NOx Sensor 1 Bank 1
P2201 00 [096] - Implausible Signal
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 203721 km
Date: 2022.11.30
Time: 08:09:59
Engine RPM: 1354.50 /min
Normed load value: 0.0 %
Vehicle speed: 68 km/h
Coolant temperature: 61 °C
Intake air temperature: 11 °C
Ambient air pressure: 950 mbar
Voltage terminal 30: 14.620 V
Unlearning counter according OBD: 40
Exh r N Ox Pres Comp NSC Ds: 22 ppm
NOx sensor 1: oxygen concentration: 0.20264
Oxygen sensor 1 bank 1: voltage raw value O2 signal: 1260.2 mV
O2 sensor 1 bank 1: adjusted oxygen value: -0.00165
EGR Solen.val.: actual value: 100.00 %
Mean injection quantity: 0.00 mg/stroke
Exhaust gas temperature sensor 1: 328.7 °C
Click to expand...
I have also a Nox Catalyst Bank 1 - efficiency too low code.9567 - NOx Sensor 2 Bank 1
P229F 00 [096] - Implausible Signal
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 194330 km
Date: 2022.07.20
Time: 16:46:01
Engine RPM: 1449.00 /min
Normed load value: 34.5 %
Vehicle speed: 88 km/h
Coolant temperature: 91 °C
Intake air temperature: 36 °C
Ambient air pressure: 950 mbar
Voltage terminal 30: 14.120 V
Unlearning counter according OBD: 20
Exh r N Ox Pres Comp No Cat2 Ds: 218 ppm
NOx-Sensor 2: O2-Concentration: 0.09336
Oxygen sensor 1 bank 1: voltage raw value O2 signal: 646.8 mV
Measured NOx conversion: 0.000
EGR Solen.val.: actual value: 34.86 %
Mean injection quantity: 6.92 mg/stroke
Exhaust gas temperature sensor 4: 348.4 °C
17277 - SCR NOx Catalyst Bank 1
P20EE 00 [237] - Efficiency too Low
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Mileage: 203518 km
Date: 2022.11.23
Time: 08:31:58
Engine RPM: 1541.00 /min
Normed load value: 56.1 %
Vehicle speed: 26 km/h
Coolant temperature: 73 °C
Intake air temperature: -1 °C
Ambient air pressure: 970 mbar
Voltage terminal 30: 14.600 V
Unlearning counter according OBD: 40
SCR efficiency test overall: 0.00 %
SCR error threshold of efficiency test: 45.00 %
SCR efficiency test 2: -1.265
SCR efficiency test 1: -1.990
Particle filter: unburned fuel calculated: 0.015
Mean temperature of SCR catalyst: 253.3 °C
Long-term adaptation of reduction agent dosage: 1.25
I logged the readings from both Nox Sensor 1 and 2;9953 - Reductant Quality Performance
P207F 00 [237] - -
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 203661 km
Date: 2022.11.27
Time: 17:00:03
Engine RPM: 1417.50 /min
Normed load value: 80.4 %
Vehicle speed: 59 km/h
Coolant temperature: 93 °C
Intake air temperature: 7 °C
Ambient air pressure: 940 mbar
Voltage terminal 30: 14.520 V
Unlearning counter according OBD: 40
Long-term adaptation of reduction agent dosage: 1.81
Measured NOx conversion range 1: 0.000
Efficiency threshold of NOx conversion range 1: 0.000
Mean temperature of SCR catalyst: 286.8 °C
NOx sensor 1: NOx concentration: 445 ppm
NOx sensor 2: NOx concentration: 312 ppm
Particle filter: unburned fuel calculated: 0.001
is there any way that Nox 2 can be higher than the pre cat Nox1? I still think I have a problem with Nox2, and have ordered a cheap aftermarket one from Amazon. Reviewing the logging, sometimes my NOX2 sensor gives readings that are higher than NOX1; sometimes it's zero, a couple times I saw -100 ppm logged.
I cleared the 350km warning by clearing the engine codes.
I graphed the log file in Openoffice... Blue is the Nox1, red is Nox 2.... Took it on a 5 minute testdrive.