P0091 P0253
MBWorld Fanatic!
Joined: Jul 2012
Posts: 1,369
Likes: 319
From: WI
GLK 250
Welcome! It sounds like you have a fueling issue. Code P0091 is a low fuel pressure warning, possibly due to a faulty low pressure pump (what we sometimes call the lift pump, in the fuel tank), and code P2053 is a misfire on cylinder #3.
When was the last time you changed your fuel filter? Have you used any fuel system cleaning agents like LiquiMoly Diesel Purge?
With low fuel pressure coming from the in-tank pump, there isn't enough fuel flow for the high pressure pump in the engine bay to properly feed all 4 cylinders. On top of that, one injector in particular (#3) is acting up. That could be a fuel return issue as well, since not all of the fuel supplied to each injector is actually burned; some of it is returned back to the tank through the return lines and helps warm up the fuel in the tank.
Both of these codes are enough to put the engine into self-protect mode, or what we call "limp home" mode. I don't know where you're located but you should look for a Euro cars independent mechanic to help you out. I would avoid a MB dealership as they will bleed you dry.
When was the last time you changed your fuel filter? Have you used any fuel system cleaning agents like LiquiMoly Diesel Purge?
With low fuel pressure coming from the in-tank pump, there isn't enough fuel flow for the high pressure pump in the engine bay to properly feed all 4 cylinders. On top of that, one injector in particular (#3) is acting up. That could be a fuel return issue as well, since not all of the fuel supplied to each injector is actually burned; some of it is returned back to the tank through the return lines and helps warm up the fuel in the tank.
Both of these codes are enough to put the engine into self-protect mode, or what we call "limp home" mode. I don't know where you're located but you should look for a Euro cars independent mechanic to help you out. I would avoid a MB dealership as they will bleed you dry.
MBWorld Fanatic!
Joined: Jul 2012
Posts: 1,369
Likes: 319
From: WI
GLK 250
Are you located in a state that mandates biodiesel? Or said differently, is biodiesel mostly what you've been fueling up with?
We need a lot more information on the car's history, service, maintenance, etc. than what you've provided. It could literally be anything fuel system related.
Most importantly, have you had the AEM work performed? Look up MB Bluetec settlement and approved emissions modification for more info.
We need a lot more information on the car's history, service, maintenance, etc. than what you've provided. It could literally be anything fuel system related.
Most importantly, have you had the AEM work performed? Look up MB Bluetec settlement and approved emissions modification for more info.
Thread Starter
Newbie
Joined: Feb 2024
Posts: 5
Likes: 0
2013 GLK250
All the warranty work was completed.
I have owned the car since July. I have had to replace the #1 exhaust temp sensor once already as it was cheaper for me to replace than to drive to the dealership.
The car has had no other issues besides the propeller shaft exploding. I fixed that myself.
I have owned the car since July. I have had to replace the #1 exhaust temp sensor once already as it was cheaper for me to replace than to drive to the dealership.
The car has had no other issues besides the propeller shaft exploding. I fixed that myself.
MBWorld Fanatic!
Joined: Jul 2012
Posts: 1,369
Likes: 319
From: WI
GLK 250
Since you've had the AEM work completed, you have a 4yr/48K mile extended warranty that covers A LOT of things, including the entire fuel system.
I would advise you make an appointment with your local MB dealership (preferrably the one that did the AEM), tell them it's fuel system related and that it should be covered under the AEM warranty.
If you have the CEL on, they will be able to see the same codes you saw. Their diagnosis should confirm repairs will be under warranty (except perhaps a new fuel filter).
Save yourself the money and headache, let them fix it for free and be adamant that it's covered.
I would advise you make an appointment with your local MB dealership (preferrably the one that did the AEM), tell them it's fuel system related and that it should be covered under the AEM warranty.
If you have the CEL on, they will be able to see the same codes you saw. Their diagnosis should confirm repairs will be under warranty (except perhaps a new fuel filter).
Save yourself the money and headache, let them fix it for free and be adamant that it's covered.
