1997 Mercedes Benz C250 Mercedes C250 TurboDiesel 1997 air

  • 1997 MERCEDES BENZ C250

Engine Mechanical problem
1997 Mercedes Benz C250 6 cyl Two Wheel Drive Automatic 180000 miles

Dear Friends,

I have a Mercedes C250 TurboDiesel 1997.
The car does not start after parking it for 1 or 2 days. I also observed air bubbles in the wires around the fuel filter.

The mechanic worked on this problem for a long time and changed the fuel tank, every plastic pipes going from the fuel tank to the engine but the problem has occured again last week. The mechanic came again and discovered that the fuel was draining back to the fuel tank when parked.

Now, our issue is to find what causes for the fuel to go back to the tank: he thinks that it might be a valve problem in the "thing" that maintains the fuel filter.

Somehow, even after changing all the pipes why is there still air in them?
what is the cause for the fuel to drain back to the tank?

P.S: I think the problem occurs when the weather is cold ( around 5 degrees)

Thanks in advance.

Do you
have the same problem?
Friday, March 12th, 2010 AT 9:30 AM

1 Reply


Hi, I have the same problem and it is the pressure valve on the back of the dieselpump also called the return valve. Replace and problem is solved.

Was this
Wednesday, September 5th, 2012 AT 5:28 PM

Please login or register to post a reply.

Recommended Guides