Audi A5 3.0 tdi auto 2008 hot starting problem

[sincl71]

Hi all, hoping for some advice as a new owner of an Audi.....

It is the model where the key is pushed into the ignition to start.

Starts and drives faultlessly when cold, but when warmed up it has an intermittent starting problem. Pushing the key to start throws up lots of error messages..... Esp fault, parking brake fault, alternator fault are 3 of them that I can remember, starter motor also does not crank over...... When it has cooled down, anything from only 5 minutes to as much as 20 it will then start perfectly.
Its currently with the dealer who sold it. They've changed the battery, and the pins behind where the key goes, plus the relay behind it, but the problem remains.

Can anyone offer some pointers at all?

 

[RS5 JON]

Suggest you get it scanned with VCDS, it should throw up a fault code for you problem.

JG

 

[desertstorm]

Is the dealer who sold it a VAG specialist ?. Changing the battery would be the first and most obvious thing to do as it was probably the first battery and as such would be due for a change. Not sure what the point of changing the parts related to the key. The main power relay would be a good one though if that is what they have changed. I would be checking things such as the engine earth strap, the fusible links on the battery connection and the connections on the power distribution panel under the bonnet.

 

[sincl71]

Suggest you get it scanned with VCDS, it should throw up a fault code for you problem.

JG

After changing the parts mentioned, zero fault codes were present. I believe it is being re read so will update if I get any more info

 

[sincl71]

Is the dealer who sold it a VAG specialist ?. Changing the battery would be the first and most obvious thing to do as it was probably the first battery and as such would be due for a change. Not sure what the point of changing the parts related to the key. The main power relay would be a good one though if that is what they have changed. I would be checking things such as the engine earth strap, the fusible links on the battery connection and the connections on the power distribution panel under the bonnet.

Not a VAG specialist, but the car has been looked at by one who recommended the changes. It's going back to the specialist again as the problem did seem cured but has reappeared..... will update with findings

 

[sincl71]

Well it's finally resolved and now with me Car ended up at Audi York (1st ones that could fit it in), and they couldn't solve it! They sent all info to Audi Germany, who diagnosed that the ecu was at fault and needed replacement. Dealer got it done and car now seems spot on!