Hi,

 

I’ve recently got myself a 2009 A3 Sport 1.9TDI. Only cost me £400 so bit of a fixer upper.

I’ve got 2 main issues with it. It smokes pretty heavily under hard acceleration, white/grey smoke. And when idling at lights I get a lot of blue smoke. Water levels are not dropping, so not likely to be head gasket.

the other problem I have is glow plug lights start flashing at 73MPH+. The car has had what I can describe as a pretty shoddy DPF delete, just based on the welding.

I have a basic OBD cable but am waiting on a Ross tech clone from china. Is anyone in or around King’s Lynn that could plug it in and have a look please? (Can’t travel due to no MOT)

The codes I managed to pull were

01134 - Alarm Horn - Malfunction detected
16346 - Control Module - Module defective
00819 - High Pressure Sensor - Short to ground
01592 - Air Quality Sensor

Any ideas regarding the smoking and limp mode would be much appreciated.

Welcome Zack,

Sounds like its burning oil somewhere, piston rings, valve seals, turbo maybe. There's a reason you only paid £400 for it.

2 hours ago, Kev-P said:

Welcome Zack,

Sounds like its burning oil somewhere, piston rings, valve seals, turbo maybe. There's a reason you only paid £400 for it.

I would be inclined to agree but the only way I can describe the smell of what comes out of that car is an ice cream van, you know the transit ones. 
I’ve also considered that it might have a really crap DPF delete too. I suppose nothing is guaranteed until I take it to someone.

 

What would you recommend?

To be honest, I'd have it plugged into a decent diagnostics before anything.

3 hours ago, Kev-P said:

To be honest, I'd have it plugged into a decent diagnostics before anything.

Agreed. Even then, the modifications may make this car a money pit.

Just now, cliffcoggin said:

Agreed. Even then, the modifications may make this car a money pit.

Personally I would have kept DPF in but obviously it was out of my hands. Not exactly cheap to put back in either. I kind of expected to spend a fair bit of money on it anyways. Already done wheel bearing and pads. That’s 100 quid straight away.

4 Faults Found:

005269 - Switch-Over Valve for EGR Cooler (N345) 
               P1495 - 000 - Open or Short to Ground
             Freeze Frame:
                    Fault Status: 01100000
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 255
                    Mileage: 231153 km
                    Time Indication: 0
                    Date: 2025.08.01
                    Time: 21:09:15
             Freeze Frame:
                    RPM: 0 /min
                    Speed: 0.0 km/h
                    Load: 0.0 %
                    Voltage: 11.63 V
                    Bin. Bits: 00000100
                    Mass Air / Rev.: 640.0 mg/str
                    Mass Air / Rev.: 0.0 mg/str
005379 - Load Signal from Alternator Term. DF 
               P1503 - 000 - Implausible Signal
             Freeze Frame:
                    Fault Status: 01110000
                    Fault Priority: 3
                    Fault Frequency: 4
                    Reset counter: 255
                    Mileage: 231167 km
                    Time Indication: 0
                    Date: 2025.08.03
                    Time: 12:18:34
             Freeze Frame:
                    RPM: 756 /min
                    Speed: 0.0 km/h
                    Load: 0.0 %
                    Voltage: 13.98 V
                    Bin. Bits: 00000111
                    Load: 0.0 %
                    (no units): 33.0
000665 - Boost Pressure Regulation 
               P0299 - 000 - Control Range Not Reached - MIL ON
             Freeze Frame:
                    Fault Status: 11110000
                    Fault Priority: 1
                    Fault Frequency: 2
                    Reset counter: 255
                    Mileage: 231255 km
                    Time Indication: 0
                    Date: 2025.08.04
                    Time: 18:57:42
             Freeze Frame:
                    RPM: 2079 /min
                    Speed: 115.0 km/h
                    Load: 59.2 %
                    Voltage: 13.98 V
                    Bin. Bits: 00000000
                    Absolute Pres.: 1948.2 mbar
                    Absolute Pres.: 1254.6 mbar
000771 - Cylinder 3 
               P0303 - 000 - Misfire Detected - Intermittent
             Freeze Frame:
                    Fault Status: 00110000
                    Fault Priority: 3
                    Fault Frequency: 1
                    Reset counter: 255
                    Mileage: 231561 km
                    Time Indication: 0
                    Date: 2025.08.08
                    Time: 17:05:05
             Freeze Frame:
                    RPM: 777 /min
                    Speed: 0.0 km/h
                    Load: 0.0 %
                    Voltage: 14.21 V
                    Inj. Quantity: 2.96 mg/str
                    Temperature: 66.6°C
                    (no units): 0.0
Readiness: 1 2 0 0 0 
-------------------------------------------------------------------------------
Address 03: ABS Brakes (J104)       Labels:. 1K0-907-379-60EC1F.clb
   Part No SW: 1K0 907 379 AH    HW: 1K0 907 379 AH
   Component: ESP MK60EC1   H31 0107  
   Revision: 00H31001    
   Coding: 13422012492600FFC80E04E7921E0081380000
   Shop #: WSC 40142 001 1048576
   VCID: 78FF5DE7CBD3425BF8-802C
1 Fault Found:
01314 - Engine Control Module 
            013 - Check DTC Memory - Intermittent
             Freeze Frame:
                    Fault Status: 00101101
                    Fault Priority: 2
                    Fault Frequency: 28
                    Reset counter: 250
                    Mileage: 231192 km
                    Time Indication: 0
                    Date: 2025.08.03
                    Time: 21:04:52
             Freeze Frame:
                    Count: 0
                    Count: 32768
                    Count: 4608
                    Count: 8193
                    Count: 50484
                    Count: 0
                    Count: 0
                    Count: 0
-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 8P0-820-043.lbl
   Part No SW: 8P0 820 043 BG    HW: 8P0 820 043 BG
   Component: KlimavollautomatH09 0100  
   Revision: 000733      Serial number: 8P0820043BG   
   Shop #: WSC 00000 000 00000
   VCID: 72EB6FCF6DAF280BC6-8026
2 Faults Found:
00819 - High Pressure Sensor (G65) 
            009 - Open or Short to Ground
             Freeze Frame:
                    Fault Status: 01101001
                    Fault Priority: 3
                    Fault Frequency: 189
                    Reset counter: 211
                    Mileage: 235093 km
                    Time Indication: 0
                    Date: 2025.02.24
                    Time: 02:25:28
             Freeze Frame:
                    Temperature: 11.0°C
                    Voltage: 12.40 V
                    RPM: 0 /min
                    Load: 0.0 %
                    Load: 9.0 %
01592 - Air Quality Sensor (G238) 
            007 - Short to Ground
             Freeze Frame:
                    Fault Status: 01100111
                    Fault Priority: 3
                    Fault Frequency: 254
                    Reset counter: 207
                    Mileage: 170405 km
                    Time Indication: 0
                    Date: 2017.02.04
                    Time: 11:36:26
             Freeze Frame:
                    Temperature: 4.5°C
-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels:. 8P0-907-279-30-H.lbl
   Part No SW: 8P0 907 279 N    HW: 8P0 907 279 N
   Component: Bordnetz-SG     H54 2801  
   Revision: 00H54000    Serial number: 00000009564452
   Coding: 11A82F81B0141380EF00001C0000000000084E0564010403002800000000
   Shop #: WSC 06314 000 08192
   VCID: 489FED273BB3F2DB48-801C
   Subsystem 1 - Part No: 8P2 955 119 F  Labels: 1KX-955-119.CLB
   Component: Wischer AU350   H10 0040  
   Coding: 00056595
   Shop #: WSC 06314  
3 Faults Found:
01117 - Generator Terminal DF Load Signal 
            008 - Implausible Signal - Intermittent
             Freeze Frame:
                    Fault Status: 00101000
                    Fault Priority: 6
                    Fault Frequency: 7
                    Reset counter: 249
                    Mileage: 231210 km
                    Time Indication: 0
                    Date: 2025.08.04
                    Time: 15:27:00
             Freeze Frame:
                        ON
                    Voltage: 12.40 V
                        OFF
                        ON
                        OFF
                        OFF
                        OFF

So I got a VCDS cable and this is the relevant faults it throws. Other faults are AC and window switches etc.
I've just gave the car full service including oil, filters and glow plugs. Anyone suggest what to check on the car physically based on these fault codes?