Extra long crank than runs perfect, 2013 c250 1.8t
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C250
Extra long crank than runs perfect, 2013 c250 1.8t
It started doing this suddenly. Every time the ignition is turned off and restarted, the engine cranks for 8 seconds before catching and running perfectly.
Have a p0002 code for fuel pressure. Seems like the the pressure regulator isnt holding pressure after shutdown
This means a new hp fuel pump, or if something else to look for? The HPFP has a regulator built in
Have a p0002 code for fuel pressure. Seems like the the pressure regulator isnt holding pressure after shutdown
This means a new hp fuel pump, or if something else to look for? The HPFP has a regulator built in
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From: SC
W204 2013 C250 CGI
Probably the HPFP but there is also a fuel pressure regulator sensor on the fuel rail. I would think the ECU would give a specific code for the sensor if it was the problem though. I found this document referencing a fuel issue on the c250 but I'm not sure if you are experiencing these issues. https://static.nhtsa.gov/odi/tsbs/20...51540-9685.pdf
I feel like maybe they released this software though to cover up the fuel pump failures and make them last a little longer but it's worth looking at.
I feel like maybe they released this software though to cover up the fuel pump failures and make them last a little longer but it's worth looking at.
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C250
Expansion on the problem. Fuel pressure was down at 50psi even after the car started. Idle was fine and the car could be driven around but power was low. Ran fine otherwise.
If let run long enough, spiking the RPM to get the fuel pump turning faster, after 20 minutes the car would run and start great. 20 mins every time. Like there was air in the high pressure system that bled out. Takes awhile.
It continues to start and run great for an hour or so afterward. Next day it's exactly the same. Low pressure and takes 8 seconds to start.
Replaced the fuel pump, it's a little better but still the same problem.
Seems like its losing pressure somewhere. Maybe through leaking injectors?
Is there a return line on the high pressure system or possibly leak back through the pump?
If let run long enough, spiking the RPM to get the fuel pump turning faster, after 20 minutes the car would run and start great. 20 mins every time. Like there was air in the high pressure system that bled out. Takes awhile.
It continues to start and run great for an hour or so afterward. Next day it's exactly the same. Low pressure and takes 8 seconds to start.
Replaced the fuel pump, it's a little better but still the same problem.
Seems like its losing pressure somewhere. Maybe through leaking injectors?
Is there a return line on the high pressure system or possibly leak back through the pump?
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C250
Fuel pressure is
~50psi when starting cold and after startup
~1000 psi when running after it
~200 psi after shutdown and keeps dropping slowly afterward
~50psi when starting cold and after startup
~1000 psi when running after it
~200 psi after shutdown and keeps dropping slowly afterward
Last edited by Russell West; Feb 8, 2021 at 05:43 PM.
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From: SC
W204 2013 C250 CGI
Considering you replaced the pump it shouldn't be losing pressure unless there is a problem with the fuel lines or injectors..I would think. Your hpfp may not be getting enough fuel to build pressure which could be caused by the low pressure fuel pump and filter assembly. I've attached some diagrams from EPC of the fuel system.
Last edited by mercjames; Mar 7, 2022 at 09:15 PM.
Thread Starter
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C250
Considering you replaced the pump it shouldn't be losing pressure unless there is a problem with the fuel lines or injectors..I would think. Your hpfp may not be getting enough fuel to build pressure which could be caused by the low pressure fuel pump and filter assembly. I've attached some diagrams from EPC of the fuel system.
Engine has good power after 30 minutes of driving. Everytime. And low pressure fuel is always there quick. Longer the engine stays off the worse it runs. Feels like rail gets air in it.
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C250
After car sit for many hours, car has the long crank condition and fuel pressure stays at 55psi for 10 minutes. Runs and idles smooth but no power.
After bumping Rpm up and down a bit, I see pressure fluctuate up to 300 but drops back down when let off gas.
Keeps improving then after running for 30 minutes pressure stays around 1000+ and power is solid
After shutoff, restart is quick and power still there.
So really seems like fuel is leaking out or back somewhere. No exterior fuel smells.
After bumping Rpm up and down a bit, I see pressure fluctuate up to 300 but drops back down when let off gas.
Keeps improving then after running for 30 minutes pressure stays around 1000+ and power is solid
After shutoff, restart is quick and power still there.
So really seems like fuel is leaking out or back somewhere. No exterior fuel smells.
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Newbie
Joined: Sep 2020
Posts: 12
Likes: 0
From: SC
W204 2013 C250 CGI
After car sit for many hours, car has the long crank condition and fuel pressure stays at 55psi for 10 minutes. Runs and idles smooth but no power.
After bumping Rpm up and down a bit, I see pressure fluctuate up to 300 but drops back down when let off gas.
Keeps improving then after running for 30 minutes pressure stays around 1000+ and power is solid
After shutoff, restart is quick and power still there.
So really seems like fuel is leaking out or back somewhere. No exterior fuel smells.
After bumping Rpm up and down a bit, I see pressure fluctuate up to 300 but drops back down when let off gas.
Keeps improving then after running for 30 minutes pressure stays around 1000+ and power is solid
After shutoff, restart is quick and power still there.
So really seems like fuel is leaking out or back somewhere. No exterior fuel smells.
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