12 ML350 CEL P0087 & CYL 2,3 MISFIRE
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Joined: Aug 2023
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2012 Mercedes ML350
12 ML350 CEL P0087 & CYL 2,3 MISFIRE
Hey everyone so i've recently been having issues with my 2012 Mercedes ML350 it started having long starts and shaking alot. Scanned the vehicle and got P0087 FUEL PRESSURE IN SYSTEM TOO LOW, P0302 MISFIRE CYL 2, P0303 MISFIRE CYL 3 P0300 AND P1CCF HIGH PRESSURE COULD NOT BE BUILT UP DURING ENGINE START. After reading a few posts and checking the fuel pressure i decided to change out the HPFP & 6 SPARK PLUGS W/6 COILS.
After that the truck ran fin for 2 days then it started shaking worse that before. I checked the codes again and I got P0087 and now Cyl 1 & 2 misfire codes. i checked the rail pressure with the scanner and it reads 149-152bar but only while idling. koeo i wasnt getting any reading from the rail.
So I went ahead and change the fuel rail pressure sensor and the in tank fuel pump. Now with the koeo i get 49psi at the rail w/ the fuel gauge But im still getting p0087 and cyl 1,2 misfires at this point i dont know what else to do if anyone has any suggestions i'd greatly appreciate it.
After that the truck ran fin for 2 days then it started shaking worse that before. I checked the codes again and I got P0087 and now Cyl 1 & 2 misfire codes. i checked the rail pressure with the scanner and it reads 149-152bar but only while idling. koeo i wasnt getting any reading from the rail.
So I went ahead and change the fuel rail pressure sensor and the in tank fuel pump. Now with the koeo i get 49psi at the rail w/ the fuel gauge But im still getting p0087 and cyl 1,2 misfires at this point i dont know what else to do if anyone has any suggestions i'd greatly appreciate it.
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Low primary fuel pressure
Hey everyone so i've recently been having issues with my 2012 Mercedes ML350 it started having long starts and shaking alot. Scanned the vehicle and got P0087 FUEL PRESSURE IN SYSTEM TOO LOW, P0302 MISFIRE CYL 2, P0303 MISFIRE CYL 3 P0300 AND P1CCF HIGH PRESSURE COULD NOT BE BUILT UP DURING ENGINE START. After reading a few posts and checking the fuel pressure i decided to change out the HPFP & 6 SPARK PLUGS W/6 COILS.
After that the truck ran fin for 2 days then it started shaking worse that before. I checked the codes again and I got P0087 and now Cyl 1 & 2 misfire codes. i checked the rail pressure with the scanner and it reads 149-152bar but only while idling. koeo i wasnt getting any reading from the rail.
So I went ahead and change the fuel rail pressure sensor and the in tank fuel pump. Now with the koeo i get 49psi at the rail w/ the fuel gauge But im still getting p0087 and cyl 1,2 misfires at this point i dont know what else to do if anyone has any suggestions i'd greatly appreciate it.
After that the truck ran fin for 2 days then it started shaking worse that before. I checked the codes again and I got P0087 and now Cyl 1 & 2 misfire codes. i checked the rail pressure with the scanner and it reads 149-152bar but only while idling. koeo i wasnt getting any reading from the rail.
So I went ahead and change the fuel rail pressure sensor and the in tank fuel pump. Now with the koeo i get 49psi at the rail w/ the fuel gauge But im still getting p0087 and cyl 1,2 misfires at this point i dont know what else to do if anyone has any suggestions i'd greatly appreciate it.
HPFP
HPFSensor
LPFP
(tank Filter?)
You can disregard the misfirings. They are directly caused by the low pressure.
Let's not bother with fuel trims.... I'd focus on the low pressure fuel pump now.
What's the current mileage ?
What type of pump, 3-Ph right?
Make sure you have equal power delivered to each pump phase winding. Controller may be toast or need a better GND source.
Filter may be plugged up.
++++++ Tank level?
Tank level may be inbalanced L/R... fill up the fas tank to rule this one out.
🤞
Last edited by CaliBenzDriver; Aug 12, 2023 at 01:49 AM.
Thread Starter
Newbie
Joined: Aug 2023
Posts: 3
Likes: 2
2012 Mercedes ML350
You have covered pretty much all the right suspects:
HPFP
HPFSensor
LPFP
(tank Filter?)
You can disregard the misfirings. They are directly caused by the low pressure.
Let's not bother with fuel trims.... I'd focus on the low pressure fuel pump now.
What's the current mileage ?
What type of pump, 3-Ph right?
Make sure you have equal power delivered to each pump phase winding. Controller may be toast or need a better GND source.
Filter may be plugged up.
++++++ Tank level?
Tank level may be inbalanced L/R... fill up the fas tank to rule this one out.
🤞
HPFP
HPFSensor
LPFP
(tank Filter?)
You can disregard the misfirings. They are directly caused by the low pressure.
Let's not bother with fuel trims.... I'd focus on the low pressure fuel pump now.
What's the current mileage ?
What type of pump, 3-Ph right?
Make sure you have equal power delivered to each pump phase winding. Controller may be toast or need a better GND source.
Filter may be plugged up.
++++++ Tank level?
Tank level may be inbalanced L/R... fill up the fas tank to rule this one out.
🤞
Thread Starter
Newbie
Joined: Aug 2023
Posts: 3
Likes: 2
2012 Mercedes ML350
