[zak]

Apologies for the late reply, I've been away with restricted access to external communications. Software version of the original and replacement part is 4L0 910 18 A.

I wasn't getting any fault codes for the J644 controller.

 

[thedenz0]

Apologies for the late reply, I've been away with restricted access to external communications. Software version of the original and replacement part is 4L0 910 18 A.

I wasn't getting any fault codes for the J644 controller.

Did you ever solve this problem? I have the same exact problem and haven't been able to find a fix for it

 

[zak]

After the Audi dealer/agent replaced 2 batteries, fuel filter housing, engine earth lead, intake manifolds, high pressure fuel pump and low pressure fuel pump the problem was still the same.

I then asked them to check the injectors, which I was assured had already been checked, only to be told they found 2 faulty injectors. These were replaced a couple of months ago and the car has been starting fine since then. Problem resolved, but it took Audi 2 years!

 

[TimU]

I'm still battling my similar problem as well, long crank but I've got the added twist of plumes of white smoke out of the tailpipe when it does start. The car's in the shop at the moment and I got a call from the mechanic today saying that they pulled out the injectors and bench-tested them and some had poor flow. They have all been ultrasonically cleaned and and now flow-tested as good.

I also have an oil leak in the Turbo which could be causing the smoke, but I'm picking up the car tonight and testing it out over the next few days.

 

[TimU]

Just as an update, I finally found a solution to my problem:
Details here and here.

TL;DR:
1) A faulty Air Suspension relay was staying energised even after the ignition systems shut down. This was causing nearly a 1A drain on the battery while the car should have been off.
2) An aging starter motor was cranking slowly and pulling more current than it should have, compounding the low battery problem and causing the long crank & starting issues.

 

[Zimmz]

No

Just as an update, I finally found a solution to my problem:
Details here and here.

TL;DR:
1) A faulty Air Suspension relay was staying energised even after the ignition systems shut down. This was causing nearly a 1A drain on the battery while the car should have been off.
2) An aging starter motor was cranking slowly and pulling more current than it should have, compounding the low battery problem and causing the long crank & starting issues.

I wonder if people still get notifications for a thread this old lol.

Tim do you know if the relay was what solved your 01299 j533 power error under the battery regulator module?
I got the exact same error along with some other stuff that I think is unrelated but working on.

Like the CD player flights that never stop flashing even with power off like that tsb pdf posted I'm going to try update with the CDs on that part n even re code the battery again just to see but it's new from Audi.

It has component protection enabled from a cooked amp thanks the the shit Audi drain. That's since been replaced, codes, and component protection removed by Audi. I just wonder if that regular could have damage. Don't see a way to test it independently.