Hi, thought I'd ask the people on here, got a little problem on my Audi A3. Out of the blue yesterday, the revs just started to drop and engine cut out. Managed to get it started again, then drove no more than 10ft. same thing again. Eventually I guess the battery ran completely low. Well to cut the long story short, managed to get someone to help me jump-start it. While doing this, as soon as I let go of the accelerator the revs would completely drop and cut out again. So connected to jump-start again and then had to hold the accelerator down at 4 (x 10) revs for a little while and that seemed to do the trick.
Well at this point justed needed to get the damn car home. Managed to drive home, but along the way, everytime I'd drop the clutch and go change gears, the revs would cut all the way down and engine cut out. This happened a few times on the way home.
After running the engine for a bit, the revs still juddered when I was in neutral but seems a bit better. Revs have been a bit juddery from day 1 of buying the car (bought it 2nd hand) but never caused any problems, think its just the idling that needs sorting.
Talked to an RAC man, he thinks it could be that the battery memory is too low or it might be the problem or that the ECU is f****d/in the process dying or alternator. Seems a bit odd.
The only differences in the setup are a replaced fuse for the dipped lights (5A) (took the one from the heated window washers 10A as couldn't really drive around with no O/S headlights/breaklights).
Got a subwoofer installed in the back too, the guy who jump-started the car thinks it has something to do with that, but I highly doubt it.
Please
please someone reply and let me know what the problem might be.
Audi A3 
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