Car turbo cutting out on motorway under acceleration orange coil light appears

[JS7319]

This is happened a few times which I thought might have been down to using bad supermarket fuel, but now I'm not so sure.

If I'm doing about 65-70mph on the motorway and need to overtake the car feels like it 'coughs', like a jerk, and then the orange coil light starts flashing. Cruise control shuts off and whilst the car is still running, power on and is driving, there is no power, it cannot climb past my current speed at the time.

For me to reset this, I need to pull over turn the car on and then off again and try not to accelerate too suddenly.

I thought it might be the turbo, but not sure!

Any thoughts? Its an Audi A4 B7 2.0 TDI 170

 

[AlS3BE]

Sounds like it’s overboosting and the engine is stopping you to protect itself.
could be sticky actuator but only guessing without proper diagnosis.
have you got an obd reader and see if you can read a code?

 

[szokatlan]

i had the "same" problem before.
Your car turn into a limp mode, mostly overboost or underboost the problem.

"same"- my problem looks a bit diferent, if i hold the speed near 2000 rpm for about 1 min, in 5. or 6. gear it nod and no more speed untill i turn it off and on again.
( i can accelerate suddenly, the orange coil light never appeared)
A4 B7 2.0 PD TDI 140HP (BLB)

 

[JS7319]

Sounds like it’s overboosting and the engine is stopping you to protect itself.
could be sticky actuator but only guessing without proper diagnosis.
have you got an obd reader and see if you can read a code?

I'm going to get AA out to give me a diagnostic. If it is, what does the repair look like, what needs to be done?

i had the "same" problem before.
Your car turn into a limp mode, mostly overboost or underboost the problem.

"same"- my problem looks a bit diferent, if i hold the speed near 2000 rpm for about 1 min, in 5. or 6. gear it nod and no more speed untill i turn it off and on again.
( i can accelerate suddenly, the orange coil light never appeared)
A4 B7 2.0 PD TDI 140HP (BLB)

I've never driven the car in at a normal speed when this has happened. But I have driven the car high revs at around 60mph to clear the DPF and there's been no cut out.

 

[AlS3BE]

If it’s like the older pd engines there’s a rod that moves back and forth to control boost. This gets corroded and doesn’t move freely so you either get too much boost or too little.
not sure if the newer common rail turbos are the same.

 

[Ricky Burrows]

I've had this same problem with a previous car albeit not on an Audi but coil light come on and i needed to give the very slightest of acceleration otherwise it would start limping i managed to crawl back to the Mercedes specialist i used at the time and mine through up about 6 fault codes but in the end it was just an exhaust back pressure sensor and it triggered a few other codes in the process, point is you can guess all you like but it could be anything, get it plugged into a good scanner that's the only way of telling for sure what it is and if the shops any good there know what fault started the issue instead of replacing all the "cheapest parts first" like every pirate mechanic says to get money out of you.