Mercedes V6 300cdi diesel pressure regulator

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jsjsev
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Joined: Thu Dec 20, 2018 8:07 pm

Mercedes V6 300cdi diesel pressure regulator

Post by jsjsev »

Hello!

I got a Mercedes GL 300cdi (v6 diesel) from 2007.

It juggers at hard ish/very hard acceleration. On easy pedal it's fine.
Changed air filters and dieselfilter, diesel treatment with some better results.

After diagnostic with Foxwell obd tool, it looks like MAF is stable and turbo is not juddering that much, but the diesel high pressure is juddering alot!

I did a scoop read on Boost pressure and Dieselpressure, and you can see diesel is dropping alot even on acceleration when the turbo is rising the diesel is dropping..

Can some tell if they got some same experiance or had same fault like this before?

Added the reads on attachement.
channel A (blue) is fuel pressure, channel B (red) is boost.

Regards, Johan.
Attachments
20181220-0003.psdata
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20181220-0002.psdata
(194.45 KiB) Downloaded 383 times
20181220-0001.psdata
(305.86 KiB) Downloaded 417 times
20181220-0004.psdata
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ronw38
TwoWaves
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Posts: 65
Joined: Sun Aug 27, 2017 8:00 am

Re: Mercedes V6 300cdi diesel pressure regulator

Post by ronw38 »

Hi Johan
Your captures dont convey a lot to me as presented. In pico Help select Online Documentation click on Videos select Frank Masseys #7 and # 8 [petrol] following along those lines should give you a more definitive fuel system test , there is also a video on Air mass vs turbo . Also check the turbo charge hoses for fractures that may valve open and closed with engine torque . Cheers Ron

ronw38
TwoWaves
TwoWaves
Posts: 65
Joined: Sun Aug 27, 2017 8:00 am

Re: Mercedes V6 300cdi diesel pressure regulator

Post by ronw38 »

The last video mentioned is Air mass meter vs Rail pressure not turbo as stated . Ron

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