Hi

I have a 2004 audi 1.8t quattro but am having problems with the engine light which keeps coming on.

Based on the VAG Com it first threw up the lambarda sensor which I changed then it gave me codes which related to Coils 1 and 2 which i also replaced.

Now I am getting the code 17705 - 'pressure drop between turbo and throttle valve p1297 upper limit reached'

I then cleaned out the throttle body but still have the same issue. The car idles a little rough and it seems to be drinking alot of fuel. I have also changed the coolant temp sensor and spark plugs.

I also checked the MAF sensor by unplugging it but it still idles rough so I dont think this is causing the problem. The previous owner had already replaced the diverter valve and I had a local mechanic check for air leaks via a smoke test but there were no signs of a visible leak

Can anyone help? I am running out of ideas and cash

 

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
o 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
o If the breather valve is faulty, full engine vacuum is typically found when removing the oil cap at idle.

 

Thanks for the info

I guess I will need to have a look at the pipes again for a possible air leak and maybe the boost pressure control valve

Thanks for your help