2007 pd170 a3 no power, intermittently wont rev above 3k

[avants2turbo]

my sister popped over earlier with her ailing A3 pd170

seems shes been having issues with it recently, sometimes with wont rev beyond 3000 even at a standstill, and then it will, but I drove it, and it totally gutless, wont rev with load, flags uphill, even changing down several gears.

we had cleaned the vanes on the turbo months ago with the old oven cleaner trick, and the actuator was working perfectly.

plugged it into vcds today, no codes (engine related) there is a code flashes up, says edc fault (i think) and the traction control light is on also

removed the egr, anti shudder valve and the inlet manifold, cleaned them all thoroughly, the swirl flap on the manifold was a bit gummed up, but cleaned it and it all moves freely

i tried unplugging the maf sensor, no different, the front boost hose that feeds the anti shudder valve/egr valve etc there was a lot of oil around it, removed it and the seal is blown, the o ring is loose, so cleaned it all up, replaced the seal, no different, this got me thinking, so started the car with the boost hose disconnected and got my sister to rev it, there is boost being produced, is there any chance the cat is blocked? if its producing boost, but it cant going anywhere?

the other thing, when we went to restart it after removing the inlet, egr etc it refused to start, turned over and over, and then the engine note changed, sounded like a car with no compression trying to start?

 

[bobby singh]

Maybe someone deleted the dpf from the map but physically left it inside?
I would put a standard map on, drive the car for while and then check for errors.

EDC fault is the ECU. Check for water damage

 

[avants2turbo]

Maybe someone deleted the dpf from the map but physically left it inside?
I would put a standard map on, drive the car for while and then check for errors.

EDC fault is the ECU. Check for water damage

my mistake, not an edc fault, its esp, the brake pressure switch wiring is faulty

the DPF was still full, very blocked, but its now no longer full

gutted the dpf, and its made zero difference!

when I try and read boost pressure in real time, the demanded is moving all over as you would expect, but the actual value doesnt move, it stays a 200.2mb

could the map sensor be faulty?

 

[AJ2706]

my mistake, not an edc fault, its esp, the brake pressure switch wiring is faulty

the DPF was still full, very blocked, but its now no longer full

gutted the dpf, and its made zero difference!

when I try and read boost pressure in real time, the demanded is moving all over as you would expect, but the actual value doesnt move, it stays a 200.2mb

could the map sensor be faulty?

hi @avants2turbo. Did you figure this out? im at the stage where id drive mine into a wall lol. Basically looking to do the oven cleaner trick, but need some help physically as im too worried ill mess it up! are you near London/kent by any chance and could give a hand. hoping it would cure intermittent power and limp mode on load, 4th gear 2.5k revs! Im still getting boost regulation codes and throwing off maf readings. Whats worrying is that you have done the vanes clean and still getting pressure. Possible inlet manifold flaps are sticking with yours? Checked that? Id be inclined to do the same. Sometimes even better to get a new inlet manifold or a delete (think darkside devlopments sell one)

 

[Peaky]

Check all the hoses even the couplers they wear against the clip. Are you getting any boost upto 2000.

 

[aqibi2000]

You've very likely got a vacuum leak, fix that then the turbo will work.

If you are competent with the hoses, you can do a vacuum suction test, start with testing the inlet - swirl flap actuator for leaking vacuum (number 6) or with engine running connect vac gauge and see if there is 100 mm/Hg

 

[Rid]

Hi all
I’ve got the same issue on A4 2.0tdi 170, engine code BRD.
I’ve checked all the vac system for leaks and that actuators all work. I did replace the turbo control valve as it didn’t hold vac solidly when disconnected; but neither did a brand new pierburg one!
I cleaned loads of gum out of the inlet manifold and flaps and egr valve, the “throttle” body was clean (it looked newish) and I have fed it some injector cleaner; end result it pulls way way better, ticks over smoother but.. it still occasionally goes into limp mode with fault code P0299 and sometimes won’t rev past 3000...
I’ve run out of ideas, so would appreciate any suggestions.
Cheers