danil_karmiev

thank u
i think so as well
Wil update when im back

danil_karmiev

i know it doesn’t prime because i can hear it when it does

SICAMG

And the fuel pressure test shows pressure or nothing at all ?

danil_karmiev

Hey everyone
replaced the crank position sensor, started right up
pumps prime every time i turn the key
thank u all
stay healthy, i ve been sick couldnt get to it earlier

danil_karmiev

Happy new year everyone
So the issue came back im leaning towards the fuel pump replacement because i also hear it whine alot when it works. Also getting 17aft at WOT. Normal drive &idle 14-15

Pmarino

You replaced the filter in the sending unit....claimed it was "filthy"..... Put in a new filter and said every thing was fine.....except it wasn't.

Then you replaced the CPS and every thing was fine...except it wasn't (I tried to deter you from this.... but no worries, it's a cheap part and should be a 100k maintenance item (IMO)

Barry gave you good trouble shooting instructions to check the pump's....Out come?

It is quite common to fry one of the fuel pumps, due to the stress (increased amperage draw) of the pump pushing through a clogged filter. This happened to me. it did not fry the relay but kept blowing the fuse. I decided to replace both of my pumps and baskets. You can try replacing just one.

Anyway.... IMO... you are going to have to go back in both access ports of the saddle tank and check both fuel pumps and sock filters. Also you have to check the sender unit.
Hopefully you have a 1/4 tank of fuel or less

https://mbworld.org/forums/w211-amg/...tenance-2.html

https://mbworld.org/forums/w211-amg/683695-confirming-fuel-pump-r-r.html

https://mbworld.org/forums/mercedes-tech-talk/587558-engine-dies-multiple-not-cps-no-dtcs-ideas.html

SICAMG

So just for more information what is the fuel pressure reading when AFR shoots to 17 to 1 ?

bbirdwell

FWIW, that describes one fuel pump non-functional or mis-wired so it is running backwards. Assuming an '03 to '05 model, if the relay was bad, both pumps would fail and the car's engine would quit running. With both pumps running, fuel pressure should be approximately 5 Bar at full throttle. With one pump failed or running backwards, the fuel pressure will drop into the 3.0-3.6 Bar range (IIRC). Will have to go back into the thread about "verify parts after fuel pumps replacement" from several years ago.
EDIT: It was in a thread on fuel pressure by "BoostedAero".
A little bit of troubleshooting and we can figure this out...

PARADOX_sf

This might help:

danil_karmiev

Hey everyone
thank u again for replying to my weird thread lol
so i have few updates
with all the help especially Bbirdwell ( you are the man) i was able to figure few things out…

when my local MB dealer did my fuel tank and components, they refused to replace fried connector on top of the fuel pumps lid
so I ordered one on ebay and my local shop ppl wired it up for me.I was running stock daily back then and didnt really use its power due to other issues with transmission valve body soledoids. I didnt have afr gauge or any data logging. Long story short with bbirdwells hint I realized that It could have been miswired. And it was indeed. My afr now is much better. Around 12.5. I know its not perfect like 11.5 but for me its night snd day to what it was.

about the starting issue, I realized that I have replaced the wrong relay. Someone turned the sockets upside down and I mistakenly replaced the relay for the air pump instead of fuel pump. Looked good initially thats why I got consufed. Now it looks a little yellow , probably from bad filter.
so no more issues there. Starts every time.

another thing that i was dealing with was ic pump. Russian MSC (moscow supercharge) sent me this great pump which i never got to work. Like all their parts have something going on headers are short, needed to weld ext. tubes, crank pulley pin kit bolt was short, so we messed up that pulley and bought modular vrp, much better piece, 2 heat exchanger has no place for hood hinch, belt they send is wrong size. I can go on and on. Yes Pavel is personally great guy very often replies to my weird questions but the parts took almost 2 years to arrive. I ordered before russian ukraine war, they didnt sent on time snd then things got hard, apparently idk.


So tonight i re installed my oem pump which was bosch 010. ( why did i even touch it) re wired back to oem connector, bled the system and Alhamdullilah
( praise to God) I really enjoyed my drive tonight.


Oh and c63 mufflers made it sound like it should, recently installed them.
thank u every one. Till next time.


ps. I have family and semi truck and trailer to take care of, sorry everything takes so long but im really happy tonight. Thank u all