2010 Audi A3 Tdi cut out and won’t restart

[Belle427]

Brother in laws car.
driving it down a duel carriageway today and he said it started to blow black smoke out of the back and lost power.
he pulled over and it’s a crank but no start condition now, had to recover it.
no codes stored on my scanner.
im struggling to know where to start with this, any Ideas would be helpful.
im going to hook up a better scanner and check fuel pressure first if I can, maybe open the fuel filter to see if it’s primed too, not sure if it uses an electric in tank pump.
at this point im assuming timing belt is intact as crank sounds normal.
Car is a 2010 model with the 140 bhp tdi common rail engine, a well serviced car with 114000 on the clock.
only other thing I’d start with is what I’d call the antI shudder valve that cuts the air off when switching off the engine that I had issues with on a 1.9 pd tdi engine once.
Thanks in advance

 

[Burnerman]

Black smoke usually means turbo failure but I think I’d definitely check the timing belt, just to rule it out.
Turbo air pipes coming adrift isn’t unknown, but they rarely prevent restarting - but the engine does go into limp home mode.
John

 

[Mr Chibs]

I'm just in the process of investigating my turbo, 2007 vw caddy van (1.9 TDi).

No black smoke, but limped home and now reduced power. Sounds like a cordless drill sound when rev'd above 2000 rpm.
Also no engine management light.

Mr Know it all suspects the Turbo impeller has play in it, so I've been recommended to strip down and look into the turbo, if there is excess play, then it's new turbo time.

Do you get codes for Turbo failure, as doesn't look like there are any sensor.

 

[Belle427]

Maybe for boost pressure but not always triggered, they do get noisier as wear develops.
hoses detaching as John says are very common, id check those first.

 

[Burnerman]

I'm just in the process of investigating my turbo, 2007 vw caddy van (1.9 TDi).

No black smoke, but limped home and now reduced power. Sounds like a cordless drill sound when rev'd above 2000 rpm.
Also no engine management light.

Mr Know it all suspects the Turbo impeller has play in it, so I've been recommended to strip down and look into the turbo, if there is excess play, then it's new turbo time.

Do you get codes for Turbo failure, as doesn't look like there are any sensor.

Some turbo’s have floating bearings which have some play until the oil pressure stabilises them.....look for any scraping where the vanes have touched the alloy casting. Not exactly foolproof but a reasonable guide!
John

 

[carmanmemoranda]

My money is on timing belt. Not unknown on these

 

[Burnerman]

Curiously enough, the belt change interval on these is 115k (or 5 years).
I don't think my nerves would let it go so long!
John

 

[Belle427]

So it looks like a shredded auxiliary belt and a piece found it's way under the belt cover.
Further investigating required but fingers crossed!

 

[carmanmemoranda]

So it looks like a shredded auxiliary belt and a piece found it's way under the belt cover.
Further investigating required but fingers crossed!

a shredded belt wouldn't cause black smoke or reduced power though.

but good to see you have found the area to concentrate on. Unfortunately it's the timing belt under the belt cover

 

[Belle427]

The timing belt has obviously jumped a couple of teeth so black smoke isn’t unusual when the timing has slipped.
im just hoping it’s not bent any valves.

 

[carmanmemoranda]

The timing belt has obviously jumped a couple of teeth so black smoke isn’t unusual when the timing has slipped.
im just hoping it’s not bent any valves.

If that engine has jumped a tooth or more I think you will be very lucky not to have internal damage. Especially if now won't start.

But good luck

 

[Belle427]

I’ve only done a pd engine before that did a similar thing, that was a crank no start. Reset the belt and timing and it was ok so I’m hoping this is similar.

 

[carmanmemoranda]

As I said, good luck.

from my experience with most vw/Audi diesel engines, 1 or 2 teeth out should start and run, even if very rough. More than that and it's big trouble.

 

[Mottie]

My neighbours Touran shredded an aux belt, it got under the cover and needed an engine rebuild.

 

[Belle427]

Reset the timing and tried it out but sadly you can hear there is no compression so it’s done some valves.
Im not going to tackle the job as it’s a nightmare to work on so will decide what to do next.
probably spares or repair as the car is only worth £3000 on a good day.