GLC 43 p0299 code
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GLC 43 p0299 code
Running into this p0299 code when hitting full throttle on my GLC 43 that then throws the car into limp mode. Any ideas on what might be the problem would be greatly appreciated. I would rather not deal with a shops as some have suspected it needs a new turbo which I find hard to believe being under 50k miles and operating fine below full throttle.
MBWorld God!
Joined: Dec 2019
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Running into this p0299 code when hitting full throttle on my GLC 43 that then throws the car into limp mode. Any ideas on what might be the problem would be greatly appreciated. I would rather not deal with a shops as some have suspected it needs a new turbo which I find hard to believe being under 50k miles and operating fine below full throttle.
https://mbworld.org/forums/c-class-w...2015-c300.html
https://mbworld.org/forums/c450-c43-...boost-jb4.html
https://mbworld.org/forums/c-class-w...299-fixed.html
MBWorld God!
Joined: Dec 2019
Posts: 32,406
Likes: 6,337
More threads that might help:
https://mbworld.org/forums/c-class-w...eparately.html
https://mbworld.org/forums/c-class-w...eleration.html
https://mbworld.org/forums/c-class-w...eparately.html
https://mbworld.org/forums/c-class-w...eleration.html
Junior Member
Joined: Jun 2007
Posts: 43
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From: Las Vegas
E400 Cabriolet
I’m going to assume that you have the M276 twin turbo.
Based on that recommendation you should see what the C43 enthusiasts are talking about.
start with this thread
C43 with low boost pressure
To answer your question explicitly
1. The check valve on the vacuum pump that supplies vacuum to the turbo wastegate actuator is known to fail and when it does boost will suffer
2. The MAP sensor on my M276TT failed and this sensor is how the ECU knows that you are under boost (this could be your issue)
3. The vacuum applied to the wastegate actuator is controlled by a solenoid and if it is not working properly then your boost will be affected
4. The intake air for the turbo has a diverter valve that can fail and if it does then you won’t get as much boost from your turbos (there are two valves, one for each turbo)
Take care
Paul
Based on that recommendation you should see what the C43 enthusiasts are talking about.
start with this thread
C43 with low boost pressure
To answer your question explicitly
1. The check valve on the vacuum pump that supplies vacuum to the turbo wastegate actuator is known to fail and when it does boost will suffer
2. The MAP sensor on my M276TT failed and this sensor is how the ECU knows that you are under boost (this could be your issue)
3. The vacuum applied to the wastegate actuator is controlled by a solenoid and if it is not working properly then your boost will be affected
4. The intake air for the turbo has a diverter valve that can fail and if it does then you won’t get as much boost from your turbos (there are two valves, one for each turbo)
Take care
Paul
MBWorld God!
Joined: Dec 2019
Posts: 32,406
Likes: 6,337
I’m going to assume that you have the M276 twin turbo.
Based on that recommendation you should see what the C43 enthusiasts are talking about.
start with this thread
C43 with low boost pressure
To answer your question explicitly
1. The check valve on the vacuum pump that supplies vacuum to the turbo wastegate actuator is known to fail and when it does boost will suffer
2. The MAP sensor on my M276TT failed and this sensor is how the ECU knows that you are under boost (this could be your issue)
3. The vacuum applied to the wastegate actuator is controlled by a solenoid and if it is not working properly then your boost will be affected
4. The intake air for the turbo has a diverter valve that can fail and if it does then you won’t get as much boost from your turbos (there are two valves, one for each turbo)
Take care
Paul
Based on that recommendation you should see what the C43 enthusiasts are talking about.
start with this thread
C43 with low boost pressure
To answer your question explicitly
1. The check valve on the vacuum pump that supplies vacuum to the turbo wastegate actuator is known to fail and when it does boost will suffer
2. The MAP sensor on my M276TT failed and this sensor is how the ECU knows that you are under boost (this could be your issue)
3. The vacuum applied to the wastegate actuator is controlled by a solenoid and if it is not working properly then your boost will be affected
4. The intake air for the turbo has a diverter valve that can fail and if it does then you won’t get as much boost from your turbos (there are two valves, one for each turbo)
Take care
Paul
