Hi!
I bought an A3 2.0 TDI (8PA BKD 2004) Sportback about 6 months ago, and had a fair amount of minor issues with it. The solutions were scattered around and I want to put into a single post for future reference and for others who come from Google. I will try to go chronologically.
Hot start problem
Basically what happens is you drive around, stop and turn off the car, try to start it up again, and it takes more than usual to catch on. This can be easily fixed by adjusting a value with VAG-COM (VCDS)
Overboosting and sticking vanes
I was going pretty fast in 6th and suddenly the car went into limp mode. After hooking it up to VCDS, it spat out the following log.
16618 - Boost Pressure Regulation
P0234 - 000 - Limit Exceeded (Overboost Condition)
Freeze Frame:
RPM: 2436 /min
Torque: 360.0 Nm
Speed: 127.0 km/h
Load: 100.0 %
Voltage: 14.29 V
Bin. Bits: 11000000
Absolute Pres.: 2325.6 mbar
Absolute Pres.: 2590.8 mbar
After looking around I've found that this could be caused by the infamous sticking vanes problem -- where the exhaust gases clog them up and restrict their movement. One cheap solution is buying Mr. Muscle Oven Cleaner, filling up the turbo to let it brake down the carbon build up. In the meanwhile, I've found a product which doesn't require going under your car (to turbo isn't accessible from the top): Wynn's Turbo Cleaner.
We took apart the intake manifold, after the air filter, and applied Wynn's Turbo Cleaner in short bursts. After the can emptied, I went for a ride.
After this procedure, the issue hasn't returned.
Brake stiff and not responding when stationary
On a cold winter morning, I was pulling out (in reverse) from the parking lot and noticed that the brake isn't responding. It was stiff, like standing on a brick. The day before, I took the car for a wash and thought that something froze up. As the weather loosened up, the freezing proved to be a wrong theory. Again, I hit up google and found that it's probably a leaking or broken vacuum host.
Part number: 1K0612041FL
Diagram: here
It was indeed cracked. After replacing it, the brake was working well.
Insufficient air flow
Now this one caused me the most headaches. The infamous code P0401. The check engine light came up after which I've connected VAG-COM and saw:
The first suspect was the EGR valve. Again, this is clogged up by the exhaust gases over time. Its only purpose is to re-use them to avoid polluting the environment as much. It is easily accessible so we decided to take it off for a good clean. It was very very dirty. After putting it back, I've cleared the DTC. The engine was much responsive on lower RPMs. I was happy -- until I saw the check engine light pop up again.
Now the suspect was a vacuum hose leak. After inspection everything seemed fine. Thanks to NHN and this post, I was pointed to the right direction a faulty solenoid valve block. This block is situated below the left window wiper.
Part number: 6Q0 906 625
It is very pricey at almost 300 euros new. Luckily, you can buy it pretty cheap from scrap yards, eBay and such. I bought mine for 30 euros from a guy who had a whole A3 in parts. If you can't find it by searching for the part number, look for "A3 parts" or similar things in ads. They rarely write it out.
Changing it is a pretty easy job it turns out. You just remove the intake pipe which comes after the air filter, remove the central screw from its holder with a torx, disconnect the pipe jack from the left, the electric jack from the right, and pull it upside. Once it's on the table, remove the four hex screws from the holder and insert the new solenoid valve block. That's it.
Turbo whistle sound (siren)
This one is a very popular topic on the forums. The sound which apprently comes from the turbo sounds like a police siren, whining, prolonged whistle etc. This video is a good example.
Well it turns out that's the sound comes from the EGR and it was fixed with replacing the solenoid valve block, like described above.
I hope someone will find this helpful.
I bought an A3 2.0 TDI (8PA BKD 2004) Sportback about 6 months ago, and had a fair amount of minor issues with it. The solutions were scattered around and I want to put into a single post for future reference and for others who come from Google. I will try to go chronologically.
Hot start problem
Basically what happens is you drive around, stop and turn off the car, try to start it up again, and it takes more than usual to catch on. This can be easily fixed by adjusting a value with VAG-COM (VCDS)
- Engine [01] - Security Access [16] - code 12233
- Engine [01] - Adaptation [10] - channel 01
- You will see CURRENT VALUE (0) and NEW VALUE. In NEW VALUE tap annything between 0 and 300 (I've bumped it to 5 and it worked)
- Press SAVE and DONE
Overboosting and sticking vanes
I was going pretty fast in 6th and suddenly the car went into limp mode. After hooking it up to VCDS, it spat out the following log.
16618 - Boost Pressure Regulation
P0234 - 000 - Limit Exceeded (Overboost Condition)
Freeze Frame:
RPM: 2436 /min
Torque: 360.0 Nm
Speed: 127.0 km/h
Load: 100.0 %
Voltage: 14.29 V
Bin. Bits: 11000000
Absolute Pres.: 2325.6 mbar
Absolute Pres.: 2590.8 mbar
After looking around I've found that this could be caused by the infamous sticking vanes problem -- where the exhaust gases clog them up and restrict their movement. One cheap solution is buying Mr. Muscle Oven Cleaner, filling up the turbo to let it brake down the carbon build up. In the meanwhile, I've found a product which doesn't require going under your car (to turbo isn't accessible from the top): Wynn's Turbo Cleaner.
We took apart the intake manifold, after the air filter, and applied Wynn's Turbo Cleaner in short bursts. After the can emptied, I went for a ride.
After this procedure, the issue hasn't returned.
Brake stiff and not responding when stationary
On a cold winter morning, I was pulling out (in reverse) from the parking lot and noticed that the brake isn't responding. It was stiff, like standing on a brick. The day before, I took the car for a wash and thought that something froze up. As the weather loosened up, the freezing proved to be a wrong theory. Again, I hit up google and found that it's probably a leaking or broken vacuum host.
Part number: 1K0612041FL
Diagram: here
It was indeed cracked. After replacing it, the brake was working well.
Insufficient air flow
Now this one caused me the most headaches. The infamous code P0401. The check engine light came up after which I've connected VAG-COM and saw:
Address 01: Engine Labels: 03G-906-016-BKD.lbl
Control Module Part Number: 03G 906 016 FF HW: 028 101 190 5
Component and/or Version: R4 2,0L EDC 0010SG 7364
Software Coding: 0000072
Work Shop Code: WSC 30562 264 135074
VCID: 6CDDDA694F90D69
1 Fault Found:
16785 - EGR System
P0401 - 000 - Insufficient Flow
Freeze Frame:
RPM: 1764 /min
Torque: 50.0 Nm
Speed: 60.0 km/h
Load: 16.1 %
Duty Cycle: 14.7 %
Bin. Bits: 11000000
Mass Air / Rev.: 270.0 mg/str
Mass Air / Rev.: 635.0 mg/str
Control Module Part Number: 03G 906 016 FF HW: 028 101 190 5
Component and/or Version: R4 2,0L EDC 0010SG 7364
Software Coding: 0000072
Work Shop Code: WSC 30562 264 135074
VCID: 6CDDDA694F90D69
1 Fault Found:
16785 - EGR System
P0401 - 000 - Insufficient Flow
Freeze Frame:
RPM: 1764 /min
Torque: 50.0 Nm
Speed: 60.0 km/h
Load: 16.1 %
Duty Cycle: 14.7 %
Bin. Bits: 11000000
Mass Air / Rev.: 270.0 mg/str
Mass Air / Rev.: 635.0 mg/str
The first suspect was the EGR valve. Again, this is clogged up by the exhaust gases over time. Its only purpose is to re-use them to avoid polluting the environment as much. It is easily accessible so we decided to take it off for a good clean. It was very very dirty. After putting it back, I've cleared the DTC. The engine was much responsive on lower RPMs. I was happy -- until I saw the check engine light pop up again.
Now the suspect was a vacuum hose leak. After inspection everything seemed fine. Thanks to NHN and this post, I was pointed to the right direction a faulty solenoid valve block. This block is situated below the left window wiper.
Part number: 6Q0 906 625
It is very pricey at almost 300 euros new. Luckily, you can buy it pretty cheap from scrap yards, eBay and such. I bought mine for 30 euros from a guy who had a whole A3 in parts. If you can't find it by searching for the part number, look for "A3 parts" or similar things in ads. They rarely write it out.
Changing it is a pretty easy job it turns out. You just remove the intake pipe which comes after the air filter, remove the central screw from its holder with a torx, disconnect the pipe jack from the left, the electric jack from the right, and pull it upside. Once it's on the table, remove the four hex screws from the holder and insert the new solenoid valve block. That's it.
Turbo whistle sound (siren)
This one is a very popular topic on the forums. The sound which apprently comes from the turbo sounds like a police siren, whining, prolonged whistle etc. This video is a good example.
Well it turns out that's the sound comes from the EGR and it was fixed with replacing the solenoid valve block, like described above.
I hope someone will find this helpful.
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