Okay, I’m new here and at wits end! Symptom; 2010 ML 350 blutec with about 90,000 miles, Over a period of about a month engine progressively got harder to start and then would not fire up. I took it to a secondary Mercedes shop who I trust and have used before. They replaced fuel filter, checked fuel pressure, fuel pressure checked at the tank read correct, but dropped near the hi pressure pump. A new OEM hi pressure pump installed but didn't correct the pressure or starting issue. Pressure check again showed a drop at the drivers side fuel rail. A new OEM fuel rail installed but still didn't correct the problem but still showed a drop at the fuek rail. The engine will fire up with a few shots of starting fluid. I took the car to the Mercedes dealership and was charged $1000 dollars for diagnosing and timing the new hi pressure pump which still did not correct the fuel pressure or starting issue. They concluded that the fuel pump in the tank needs replacing but previous check, pump had the required pressure. Has anyone experienced this? Could the problem be in the cars computer? Any tips or advice would be greatly appreciated!

 

moved to W164 forum...

 

Did you pay the mechanic and M/B even though the car still does not start?

 

Yes, the first mechanic wouldn't go any further after the fuel filter, hi pressure pump and fuel rail didn't correct it but made some adjustments on the repair bill.

 

I had problem with starting of my old gl450 2007…took long cranking to start up. I thought the battery was weak and replaced new one but no help, then replaced fuel pump but same thing.

Turned out to be a year or 2 later, The starter was completed dead, replaced Starter and car fired up 1st crank every time.
Hope this help to narrow down your problem.

 

Did M/B make you pay anything? If they did, they are responsible and you should PAY NOTHING, BOY DID YOU GET SCREWED.

 

The service advisor at MB stated initially that it would be about $190. a test but that could be applied to the repair if I decided to have them repair it. But yes, you are probably right.

 

Oddly enough i had to replace the starter, which went died about two years ago.