I've seen a few threads on here regarding the intermittent cold start problem that seems to plague every B6 S4 at some time or other (Evo even experienced it on their Press car when new).
I looked everywhere for experiences (including this forum) and, eventually, bit the bullet and had the starter motor replaced. This had completely resolved the issue at a cost of £305.
My specific symptoms were:
- First thing in the morning, you turn the key and absolutely nothing happens.
- Display shows all the relevant lights.
- After between 5 and 20 minutes, you turn the key and the car bursts into life immediately.
- Once the engine had started, it's absolutely fine for the rest of the day.
- Tried different ignition keys - no difference
- After causing me to miss a couple of trains, the car once wouldn't start for 30 minutes (really cold and wet night). I called the AA and, as soon as I got off the phone, car started.
Was final straw so took to Audi Specialist.
He checked wiring and confirmed no fault was recorded using diagnostics. Fault wouldn't happen to him (Grrr). He said he was 99% sure it was the starter motor. I was sceptical but agreed to have it replaced, as it was really stopping me enjoying my V8 monster.
Dropped it off a week later, fault happened for him, he replaced the starter motor (as agreed) and it has completely resolved the issue!
I have a feeling a lot of people run into this issue but it doesn't seem to be something Audi will acknowledge. Specialist said the starter motor was ' a little lightweight and small' the size of engine and this might be why they fail. He also said it might be smaller, as there isn't much space under the bonnet! (and I expect Audi were keen to limit weight at the front end of the car).
Hope this helps someone tearing their hair out!
