EML comes on every few weeks with 3 errors

[Dark Horse]

Engine Management Light has come on twice now over the last month. VAG-COM reports the following both times:

3 Faults Found:
16891 - Idle Control System RPM Higher than Expected.
            P0507 - 001 - Upper Limit Exceeded
17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
            P1297 - 001 - Upper Limit Exceeded
17544 - Fuel Trim: Bank 1 (Add): System too Lean
            P1136 - 001 - Upper Limit Exceeded
Readiness: 0000 1000

Both times the EML has come on shortly after starting the car and it being driven in crawling traffic. Idling is either erratic or higher than expected but there doesn't seem to be any loss of power and there are no misfires. Car seems to drive just fine without going into limp-home mode and after I've cleared the codes, the car is OK for a few weeks until the EML comes back on.

Other than checking the hoses and diverter valve, can anyone help in suggesting what the problem could be and rough estimate as to how much it'd cost to get it fixed at the dealers or an indie? If it helps, VAG-COM reported just the 17544 "System too lean" error code last year after the MT went but this didn't cause the EML to come on so I just ignored it.

[bez101]

16891/P0507/001287 - Idle Control System RPM: Higher than Expected.

Possible Symptoms

• Malfunction Indicator Lamp (MIL) active

Possible Causes

• Throttle Valve Control Module (J338) dirty/faulty
• Wiring/Connector(s) from/to Throttle Valve Control Module (J338)
• Vacuum Leak

Possible Solutions

• Check Throttle Valve Control Module (J338)
• Check Wiring/Connector(s) from/to Throttle Valve Control Module (J338)
• Check Intake System for Leaks

Special Notes

• When found in the NAR 2.0T (BPY) check RVUTB: 01-09-03 or 2018919 for updated Crankcase Breather Valve
  
  • If the breather valve is faulty, full engine vacuum is typically found when removing the oil cap at idle.

17705/P1297/004759 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)

Possible Symptoms

• Malfunction Indicator Light (MIL) ON
• Power Loss

Possible Causes

• Leaking Hoses and/or Pipes between Components
• Boost Pressure Control Valve (N249) faulty
• Diverter Valve faulty
• Throttle Body dirty

Possible Solutions

• Check Hoses and Pipes between Components
• Check / Replace Boost Pressure Control Valve (N249)
• Check / Replace Diverter Valve
• Check / Clean Throttle Body
  
  • Perform Throttle Body Alignment

Special Notes

• Did anyone install an extra (wrong) dump valve?
• When found in the NAR 2.0T (BPY) check RVUTB: 01-09-03 or 2018919 for updated Crankcase Breather Valve
  
  • If the breather valve is faulty, full engine vacuum is typically found when removing the oil cap at idle.

17544/P1136/004406 - Fuel Trim: Bank 1 (Add): System too Lean

Possible Solutions

• Check Mass Air Flow (MAF) Sensor
• Check Fuel Pressure Regulator
• Check Fuel Pump
• Check Intake/Exhaust System for Leaks
• Check Secondary Air Injection for Leaks
• Check Vacuum Lines for Leaks

Special Notes

• Fuel Trim Info
• When this fault is stored and external vacuum leaks are not found, less obvious problems may be present:
  
  • Check Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80)
  • Check Brake Booster and Hoses
  • Check Electric Vacuum Pump ( If Applicable )
  • Check Crankcase Ventilation System for faulty components

a few things to check

[Dark Horse]

Cheers Bez, will get these looked at

[Dark Horse]

Quick update on this, checked all the hoses and couldn't find any immediate leaks. Took it to my local Audi indy and they cleaned and realigned the throttle body and also replaced the breather valve as the disc had collapsed (see attached pics).

Breather valve was seven quid, injector cleaner another fiver and together with 1.5 hours labour for everything else, total bill came to just under £130 inc.

Result is car runs and idles a lot smoother and has more power with a far more responsive throttle. When I put my foot down, it really shifts now

Indy said the throttle body was very grubby and gummed up because car wasn't driven frequently and it can happen to any motor which sounds right as I had the exact same prob with an old Nissan.

Breather valve



Breather valve showing collapsed disc

[blackpool1974]

Glad you got it sorted so fast, took me 3 indi garages and then finally took the plunge and went to Audi, cost me about £600 all in and took 6 months to find it !! had new MAF and all Vac pipes changed in the process, absolutely no info on any VW or Audi website at the time, since then loads of people having this problem, so easy to fix, but potential to cost a fortune if you follow the vagcom codes