3.0TDI Hot Start Issue, very slow cranking, fails to ignite, reproducible every time
 

On the way to get my headlights polished/restored today (which was a success+++), I stopped at the ATM for for the cash and when I got back in the car, the cranking was so slow but it started. Now, it has been doing this for about a year, not very often that I stop for such a short time, but when I do, it goes wuh wuh wuh wuh but starts, sometimes takes 2-3 times as the starter cuts out. The dash and DRL lights also dim a lot during this, much more than on a cold start, they nearly go completely off and somethings reset like bluetooth connections so voltage is is going too low.

Anyway a few minutes later, I was a bit ahead of schedule, so I parked up and checked emails and stuff, came to start car and wuh wuh try again wuh wuh.
Tried 20 times over say 10 minutes and by now was late for my appointment.
I was only 0.3 miles away so called him and he came out to jump start me and he checked the voltage on the battery it was 12.1v, tried to start it to see how far it dipped and it started normally without needing a jump start.

Went to my appointment for say an hour and started fine afterwards.

I'm sure it's not the battery, it seems to be the starter jamming (as the lights go so so dim and it cranks in a laboured slow way). Also, after this, it will start later on when cooled.

I am also thinking could it be earth straps? Can't say I have noticed any but I seem to recall A8chick having this issue about 5-6 years ago but can't find it.

This seems to be a commonish problem on these engines, but find lots of questions and not many answers, can anyone shed any light?

PS no codes about jammed starter.

Oooh there was a thread about this a while ago and I think it was to do with a loose power connection somewhere - one of the footwells perhaps?

That is an odd one. Made me think of the thread about some sort of electrical connection inside the OSF wing/wheel arch. Don’t know why though. Maybe it was the heat aspect. I’m sure the connection in that thread, got hot or something similar.

http://forum.a8parts.co.uk/showthrea...ivers+footwell

Oh yes, thanks, I eventually found it. Will have a look in the morning.

That’s the thread I was thinking of. Just didn’t remember the location of the connection. Good job we have MJ!!

Thanks both - I'll take a few more photos to show where to find it and compare notes.

Any pics of your headlights, before/after? +++
Also how much did it cost

Sadly no, but it was £40. He masked off and used a cordless brushless drill with some 2 or 2.5" discs designed for small bodywork refinishing. They were velcro backed sandpaper discs, after that, foam discs that had the abrasive built in and foam polishing discs and some polish may have been autoglym and also meguires UV headlight protection. It took about 90mins to do both at a leisurely pace. I haven't had a chance to find that connector under the drivers carpet as I would need to unbolt the seat to pull up the carpet so will wait until I have more time.

Cool. Make sure you get something like 303 aeroprotectant on them regularly. Will keep it protected from UV damage

Will do thanks, also looking at some 3M protective film.