Hi 

I’ve got an a4 avant 2.0tdi 170bhp CAHA engine, when you accelerate hard it seems to cut power and dies right down There’s a bit of a rattle and the accelerator doesn’t do anything until you drop down a gear and it picks up again there’s no fault codes coming up

so far it’s had 

maf, fuel rail pressure sensors, high pressure fuel pump, in tank fuel pump, auxiliary fuel pump, crankshaft sensor, turbo and a fuel pressure regulator none of this has fixed it

ive attached a video to hopefully help show what it’s doing 

 

 

thanks 

Have you changed the map sensor and fuel regulator sensor?

Also check the intake swirl flaps...these can brake then close on their own at high boost as I found out this week .

Also be handy if you know someone with vcds... monitor live data like throttle body position, specified Vs actual readings on fuel rail ect. 

Also with the rail make sure it's legit sensors and not eBay specials as they cause issues too.

Spoke to my brother (previous owner) he has replaced the MAF, the high pressure fuel pump had a fuel regulator sensor with it so fitted that one, think I’ll have to find someone local with VCDS