2,5tdi 0550 and lack of power,after fuel filter change


Registered User
Hello. Sorry for my english, its my 3rd language.

Evrything was fine ,car has 300k, its 2000 2.5tdi 150hp automatic. After new year i decide to change fuel filter because evrything else have been changed and it was only thing that havent. So i bought new filter(swag) changed it and then wanted to get air out of sytem. I tought that tank pump should push fuel to filter but it didnt so i took out pump mess whit it, but i put it like it was and put it in back in tank. Then i pushed air out off system manualy and car started after minute of crnaking.
It was running Ok no problems , and evrything was fine. Aftee 5km it started shaking and looaing power. I could get it oved 2000rpm, i turned off and start again,and it was good agaib, drove 2km more and again could't go over 2000rpm. And it showes 0550 fault.
Couls it be main fuel pump? And why ? I didnt toch main fuel pump.


Registered User
Info below is from VCDS web site. My guess is air in the system.
I understand the pump in the tank does not supply diesel to the engine just moves fuel within the tank.
Correct procedure is to fill the filter with fuel before you re-fit and use a vacuum pump to get the air out via the output hose on the filter.

00550 - Start of Injection Regulation
00550 - Start of Injection Regulation: Control Difference
Possible Symptoms
  • Malfunction Indicator Light (MIL) ON
  • Loss of Power
  • Starting Problems
  • Transmission in Emergency Mode
Possible Causes
  • Fuel Tank incorrectly filled with Petrol or Biodiesel
  • Air/Water in Fuel System
  • Injection Timing incorrect
  • Electrical Fuel Pump faulty
Possible Solutions
  • Check Fuel Tank for Petrol and Biodiesel
    • Drain Tank and Fuel System
  • Check Fuel System for Air/Water
  • Check Fuel Supply and Return Lines for Blockage and Leaks
  • Check Electrical Fuel Pump
  • Check/Correct Injection Timing
    • Perform Basic Setting / Use TDI-Graph


Old ones are the best ones
You should fill filter before fitting, make sure plenty of fuel in tank, give it a good hard run.