So had this fault for a few months now and happens 20% of the time at around 3500 revs going uphill.Mechanic has had the turbo off and cleaned and replaced the n75 and egr valves..... anymore ideas...? its driving me mad..... and with it being a sharan the access to the turbo is crap...!!! doing my head in.. 17965/P1557/005463 - Charge Pressure Control: Positive Deviation Possible Symptoms Reduced power output Limp mode Possible Causes Boost Pressure too High Hoses/Pipes incorrect connected, disconnected, blocked or leaking Charger Pressure Control defective VNT (variable nozzle turbo): nozzles stuck Solenoid Valve for Boost Pressure Control (N75) defective Possible Solutions Check Hoses/Pipes to/between Components Check Solenoid Valve for Boost Pressure Control (N75) Check / Clean / Replace Charge Pressure Control Check / Clean mechanism for variable nozzles
Has the turbo vanes been cleaned and free'd up properly? Is vagcom seeing the correct values with the engine off and at idle ie altitude correction when off and altitude correction and 0 charge pressure? Have you done a live run with vagcom to see what boost it makes upto the limp point? Is the maf sensor in good order? Just a few things to check. Doing a live run with vcds is best to establish what various sensors are seeing at load etc.
I would also ask how well was the turbo cleaned!! I've had murders with a 1.9 tdi Golf & after sorting several other issues...the turbo worked but intermittantly. I used 3/4 bottles of wynns diesel 3 cleaner (approx 50) using a double shot (2 bottles) first. I have always been very wary of pour in fixs...but after 500miles ish the car go's brilliantly!!!! Best regards Chris 07857 224493
Don`t know how well the turbo was cleaned, he said it was free and moving smoothly...?> not done any live runs and not sure he`s upto that to be honest... I`m based in manchester does anyone know anyone else who can help to diagnose further, dont want to have to sell the car on just because of this fault.. Maf sensor unpugged the car runs **** then fine when plugged back in...? so think thats ok....?:
Points towards the turbo not operating correctly. Dont forget things expand with heat, so unless the vanes are totaly free they will seize up again. Not that your chap isnt trust worthy, but mistakes happen.
Hello i had this fault with my seat alhambra and it was the turbo the vanes were all seized up removed the turbo and sent it away to Midlands turbo and cleaned and rebuilt and tested with 1 years warranty for 185 + the vat refitted the turbo and not had any problems since so i would say turbo fault
