2021 GLE 350 code P0191
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2021 GLE 350 code P0191
Hi All............wife's 2021 GLE 350 just threw a check engine light with code P0191. Car is in limp mode. That code references a Fuel Rail Pressure Sensor fault. Anyone have experience with this before? Any help is appreciated.
I can find a part # for a Fuel Pressure Sensor that sits on top of the Fuel Pump, but cant find anything about a sensor on the fuel rails. Very little info available for this particular model.
1) is anyone aware of a fuel pressure sensor on the fuel rails? If so, do you know the part # and location?
2) how accessible is the fuel pump? Ive seen several other MB models have the pump under the rear seat. Does the same apply here?
Im more of a DIY guy, so would like to replace the sensor myself if possible vs taking it to the dealer. The sensor is only $60.
Thanks in advance
David
Thanks
David
I can find a part # for a Fuel Pressure Sensor that sits on top of the Fuel Pump, but cant find anything about a sensor on the fuel rails. Very little info available for this particular model.
1) is anyone aware of a fuel pressure sensor on the fuel rails? If so, do you know the part # and location?
2) how accessible is the fuel pump? Ive seen several other MB models have the pump under the rear seat. Does the same apply here?
Im more of a DIY guy, so would like to replace the sensor myself if possible vs taking it to the dealer. The sensor is only $60.
Thanks in advance
David
Thanks
David
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Hi All............wife's 2021 GLE 350 just threw a check engine light with code P0191. Car is in limp mode. That code references a Fuel Rail Pressure Sensor fault. Anyone have experience with this before? Any help is appreciated.
I can find a part # for a Fuel Pressure Sensor that sits on top of the Fuel Pump, but cant find anything about a sensor on the fuel rails. Very little info available for this particular model.
1) is anyone aware of a fuel pressure sensor on the fuel rails? If so, do you know the part # and location?
2) how accessible is the fuel pump? Ive seen several other MB models have the pump under the rear seat. Does the same apply here?
Im more of a DIY guy, so would like to replace the sensor myself if possible vs taking it to the dealer. The sensor is only $60.
Thanks in advance
David
l
Thanks
David
I can find a part # for a Fuel Pressure Sensor that sits on top of the Fuel Pump, but cant find anything about a sensor on the fuel rails. Very little info available for this particular model.
1) is anyone aware of a fuel pressure sensor on the fuel rails? If so, do you know the part # and location?
2) how accessible is the fuel pump? Ive seen several other MB models have the pump under the rear seat. Does the same apply here?
Im more of a DIY guy, so would like to replace the sensor myself if possible vs taking it to the dealer. The sensor is only $60.
Thanks in advance
David
l
Thanks
David
There are two distinct fuel circuits: low presure then high pressure.
Your fuel rail sensor is located under the intake plenum where the fuel rail feeds the set of injectors.
Out Of Control!!
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Bosch makes this
Use your VIN# for an exact P/N match then find a nearby supplier.
Last edited by CaliBenzDriver; Jan 6, 2026 at 03:54 PM.
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2002 E320
Fuel rail sensor
Hey I don’t know how different yours is but mine 2016 is on the drivers side rail, under the manifold cover but you can see it without removing the cover. It’s on the aft end of the rail (closer to window).
That looks like my sensor but call FCP Euro, they’ll get you sorted on part numbers. They may even have a diagram.
my HPFP is opposite corner/passenger also closer to the window on the top corner of the engine.
That looks like my sensor but call FCP Euro, they’ll get you sorted on part numbers. They may even have a diagram.
my HPFP is opposite corner/passenger also closer to the window on the top corner of the engine.
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Hey I don’t know how different yours is but mine 2016 is on the drivers side rail, under the manifold cover but you can see it without removing the cover. It’s on the aft end of the rail (closer to window).
That looks like my sensor but call FCP Euro, they’ll get you sorted on part numbers. They may even have a diagram.
my HPFP is opposite corner/passenger also closer to the window on the top corner of the engine.
That looks like my sensor but call FCP Euro, they’ll get you sorted on part numbers. They may even have a diagram.
my HPFP is opposite corner/passenger also closer to the window on the top corner of the engine.
These sensors get baked by heat soaks at engine stops just like the A/C refrigerant sensor at radiator/condenser base.
For good measure make sure LPFP is ok and not causing HPFP to actup!!
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Day before car was extremely low on gas but didn't run out. I also got a drive thru car wash . Hopefully not expensive fix.
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Not yet. I ordered the sensor but hasn't come yet. FCP Euro advised that if the sensor doesn't fix it, it's most likely the high pressure fuel pump that's causing the code.
As a temporary fix, if you have a scanner and can clear the code, it removes the CEL and takes the car out limp mode for a week or so. It does come back and you can clear again until you get it fixed.
As a temporary fix, if you have a scanner and can clear the code, it removes the CEL and takes the car out limp mode for a week or so. It does come back and you can clear again until you get it fixed.
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e55
Not yet. I ordered the sensor but hasn't come yet. FCP Euro advised that if the sensor doesn't fix it, it's most likely the high pressure fuel pump that's causing the code.
As a temporary fix, if you have a scanner and can clear the code, it removes the CEL and takes the car out limp mode for a week or so. It does come back and you can clear again until you get it fixed.
As a temporary fix, if you have a scanner and can clear the code, it removes the CEL and takes the car out limp mode for a week or so. It does come back and you can clear again until you get it fixed.
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W212 MY'14 M276-3.5NA @75kMi
No Wet Finger
Not yet. I ordered the sensor but hasn't come yet. FCP Euro advised that if the sensor doesn't fix it, it's most likely the high pressure fuel pump that's causing the code.
As a temporary fix, if you have a scanner and can clear the code, it removes the CEL and takes the car out limp mode for a week or so. It does come back and you can clear again until you get it fixed.
As a temporary fix, if you have a scanner and can clear the code, it removes the CEL and takes the car out limp mode for a week or so. It does come back and you can clear again until you get it fixed.
use your scanner to diagnose the fuel pressure reported by the ECU.
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e55
Tried clearing the codes with my Amazon scanner, no go. Towed the car to the mechanic and funny enough, my battery was the culprit. A few theories on the cause of that code, but the battery was checked and indeed low/dying. Replaced the battery and clearing the codes resolved the issue, for now at least.
Out Of Control!!
Joined: Apr 2019
Posts: 11,922
Likes: 6,775
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Tried clearing the codes with my Amazon scanner, no go. Towed the car to the mechanic and funny enough, my battery was the culprit. A few theories on the cause of that code, but the battery was checked and indeed low/dying. Replaced the battery and clearing the codes resolved the issue, for now at least.
🤞
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Hey, I just replaced my battery after this error code popped up. I had a feeling my battery was dying since I would get low battery signs for a month or so. Did changing the battery fully resolve your issue? I cleared the codes after changing the battery, so how long would I be able to tell that this resolved the issue? (Going out of the state with the car in a couple of days, so I do not want to risk it)
