D3 Intermittent Start Fault

[woodpoleman]

After 7 months we at last have a fix and the Egertons Breakdown guy was right - starter relay! I took the car to QRS Auto Service, Tattenhall for a service and (hopefully) a fix (my first visit and won't be the last). Fault was Relay J329 (370) cost £14.95 + VAT and to be on the safe side also changed J53 & J695 (381).

The fault didn't show on any scans and it seems if it doesn't nobody can be bothered to look further. My own garage, on advice from a mobile auto electrician, replaced the alternator,starter motor, comfort ECU and ignition switch. For which we will now have an interesting discussion about the bill. My local Audi recoded the ECU, refusing to until I paid for a VW battery, had the car for two separate weeks and did nothing other than start it every hour. Another local auto electrician had the car for a day suggested a (non-specific) relay at around £60.

Thanks to everybody who contributed especially Ray for the scan because it all helped narrow down the issue.

[47p2]

Thanks for the update, mine has the occasional problem of what sounds like a lazy starter motor or bad earth when the engine is up to temperature. It doesn't happen every time but if I don't do something about it I'll be left stranded in the future.

Do you know the part numbers for J329 (370), J53 & J695 (381)?

[woodpoleman]

Sounds very similar. I think the problem was J329 but the garage changed the others because I had installed a couple of used 381's. I had a job tracking down which relay/s was/were the problem.

J329 is 8D0 951 253 is colour grey and has 370 on the top. J53 & J695 are part No 431 951 253G are purple and have 381 on the top. They are located behind the trim in front of the steering column. The works manual page/drawing is A97-0403 (Google it), J329 is No3 and the other two are Nos 2 & 5. J329, which carries the power was only £14.95 plus vat the other two were 31.44 each plus VAT.

Good luck hope it works for you.

[47p2]

Thats great thanks, worth giving it a try

[woodpoleman]

At £18.00 certainly a cheaper test than an alternator, starter motor, comfort ecu, ignition switch, battery, coding and labour!!!

[woodpoleman]

Just to add - here's a couple of pictures, at the base of the large terminals of 370 it shows there's been some heat.

[M-A8]

Great result mate
Is your problem fully solved now ??

[Architex_mA8tey]

Originally Posted by 47p2

Thanks for the update, mine has the occasional problem of what sounds like a lazy starter motor or bad earth when the engine is up to temperature. It doesn't happen every time but if I don't do something about it I'll be left stranded in the future.

Do you know the part numbers for J329 (370), J53 & J695 (381)?

This could also be crankshaft position sensor which happened on mine, always started fine from cold but didnt fire up at all when warm/hot sometimes.
Gradually got worse until replaced after it failed completely one day

[47p2]

Normal pattern for a faulty crankshaft sensor would be that the engine would turn over as usual but fail to start.

[Architex_mA8tey]

Originally Posted by 47p2

Normal pattern for a faulty crankshaft sensor would be that the engine would turn over as usual but fail to start.

sorry you're right, but does yours do that as mine is already fixed lol ?