2012 E250d c207

[gjw442]

Hi guys
My car goes into limp mode when it revs over 3k.
It's slightly slow to start but will always start and runs OK till over 3k pm then says P087 low fuel pressure.
It went to garage who said it was the fuel rail sensors , but I changed them both and its still the same .
I did how notice when the ignition is turned on the fuel rail return pipe nesr the fuel rail buzzing for quite along time then stops like there's a problem to build up pressure . It's about 20 secs before it stops and would presume it should be a couple of secs.
I've attached a pic of which pipe is making the noise/fuel flowing
If anyone can help will be really grateful
Thanks

 

[onefortheroad]

It runs for 20 seconds it's priming the system . Normal

Has the fuel filter been changed?

 

[gjw442]

It runs for 20 seconds it's priming the system . Normal

Has the fuel filter been changed?

Yes new filters.
That's what I was wondering.
So that eliminates that and the fuel rail so its now either the intank pump or the fuel quantity sensor on the high pressure pump