Om642 Rail pressure too low
#1
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Hello! first,sorry for my bad english,im from finland and i just drank bottle of vodka.
anyway i didin't find help form finnish forum for my problem so i need to expand to international forums.
i have s211 om642 and it goes to limp mode when im accelerating fully,just when rpm is over 3000 and it shifts up to 3 gear.
Star gives 2047-001 ''rail pressure from quantity valve is too low'' and this is when ''cold'' engine
when engine is running warm it gives 2051-001 ''rail pressure from pressure valve is too low''
Just noticed that delivery pressure between filter and HP pump is 2,5 bar when car is at idle,is that too low? With brand new filter.
Here some list what i have done allready
-New quantity valve
-Pressure valve from fully working car
-Injector test(one was leaking,i replaced it. rest of were fine)
-Rail pressure sensor from working car
-Rail pressure test with Star,1500RPM rail pressure were 1636bar(enough?)
- DPF off.EGR off and chip tuning in.
I attach video,there i speed up from 0 to limp mode
here quick translate for video
4540(top) ENGINE RMP
4607 FUEL TEMP
4546 COOLANT TEMP
4603 RAIL PRESSURE
4612 INJECTION QUANTITY AT THIS MOMENT
982 PRESSUREVALVE
014 QUANTITY VALVE
3692 RAIL PRESSURE ADJUST (quantity valve or pressure valve)
''Ohjearvo''= What it should be
''Mittausarvot''=What it is now
Y74 is pressurevalve and Y94 is quantity valve (that you guys allready know)
Thanks for the help! now i will go to sauna and open third bottle of vodka. Then im going to figure out how to beat and burn this F-- car
anyway i didin't find help form finnish forum for my problem so i need to expand to international forums.
i have s211 om642 and it goes to limp mode when im accelerating fully,just when rpm is over 3000 and it shifts up to 3 gear.
Star gives 2047-001 ''rail pressure from quantity valve is too low'' and this is when ''cold'' engine
when engine is running warm it gives 2051-001 ''rail pressure from pressure valve is too low''
Just noticed that delivery pressure between filter and HP pump is 2,5 bar when car is at idle,is that too low? With brand new filter.
Here some list what i have done allready
-New quantity valve
-Pressure valve from fully working car
-Injector test(one was leaking,i replaced it. rest of were fine)
-Rail pressure sensor from working car
-Rail pressure test with Star,1500RPM rail pressure were 1636bar(enough?)
- DPF off.EGR off and chip tuning in.
I attach video,there i speed up from 0 to limp mode
here quick translate for video
4540(top) ENGINE RMP
4607 FUEL TEMP
4546 COOLANT TEMP
4603 RAIL PRESSURE
4612 INJECTION QUANTITY AT THIS MOMENT
982 PRESSUREVALVE
014 QUANTITY VALVE
3692 RAIL PRESSURE ADJUST (quantity valve or pressure valve)
''Ohjearvo''= What it should be
''Mittausarvot''=What it is now
Y74 is pressurevalve and Y94 is quantity valve (that you guys allready know)
Thanks for the help! now i will go to sauna and open third bottle of vodka. Then im going to figure out how to beat and burn this F-- car
#2
Found it! There is delivery fuel relief valve under the HP pump. There were tiny rock and relief valve were littlebit open all the time. I removed that rock and now its fully working! Hooray. I wrote this solution if someone has samekind problems.
The following users liked this post:
MB_FanAddict (01-24-2023)
#3
Do you have any pictures of where the rock was stuck? I am just mostly curious.
Thanks,