2014 CLA45 REDUCED PERFORMANCE
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2014 CLA45 REDUCED PERFORMANCE
Hi everyone, I’m new to the platform and have been experiencing plenty issues with my 2014 Mercedes CLA45 AMG.It has a code P026A00, the efficiency of the charge air cooler is not sufficient. Every time the code is cleared it comes right back. The performance of the car is extremely underwhelming and is extremely sluggish especially after third gear, it feels like it’s not getting any more boost. I’ve driven other CLA45 that are stock and feel much faster although mine has a downpipe and a mild tune. Even from first gear the car doesn’t pull how it should. During my ownership I’ve already had to replace the transmission, the PCV system, and the thermostat. I’ve also got a P062800 Code, the output for the fuel pump has a short circuit to ground. The final code is also fuel related, P008B00, the pressure in the fuel low pressure circuit is too high. I have not noticed any coolant leaks since the thermostat was replaced although it did completely drain out of the system when a hose popped off just previous to the thermostat service during a long drive.
I need some guidance on what steps to take next and if anyone has experienced anything similar. Any help is greatly appreciated.
I need some guidance on what steps to take next and if anyone has experienced anything similar. Any help is greatly appreciated.
Newbie
Joined: Apr 2025
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Mercedes CLA 250
Intercooler
Since you mentioned a hose popped off and coolant was lost, double check for any trapped air in the intercooler coolant loop, air pockets can significantly reduce cooling efficiency. Also inspect the intercooler pump; if it's weak or failing, you'll get that exact code and symptoms.
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From: San Antonio, USA
C204 C63 P31, A205 C63, C204 C63 507 Edition, C117 CLA 45
I just got this code, from my research the turbo was designed without an adequate bypass valve. Over time the bypass valve begins to fail, normally the bypass valve sticks inside of the turbo. When you let off the throttle abruptly like a n/a car, the turbo gets surged, then the computer picks up on the changes in the adaptations which pulls boost to preserve the turbo. The solution that I am going to try is the Weistec bypass valve. It will vent excess air to atmosphere instead of back into the turbo housing. It's a poor turbo package design, so this is only a temporary fix and will prevent the codes, in my opinion. However it's only a matter of time before the turbo fails, depending on what mileage you got the car at and how the previous owner(s) drove the car.
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I just got this code, from my research the turbo was designed without an adequate bypass valve. Over time the bypass valve begins to fail, normally the bypass valve sticks inside of the turbo. When you let off the throttle abruptly like a n/a car, the turbo gets surged, then the computer picks up on the changes in the adaptations which pulls boost to preserve the turbo. The solution that I am going to try is the Weistec bypass valve. It will vent excess air to atmosphere instead of back into the turbo housing. It's a poor turbo package design, so this is only a temporary fix and will prevent the codes, in my opinion. However it's only a matter of time before the turbo fails, depending on what mileage you got the car at and how the previous owner(s) drove the car.
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Joined: Aug 2021
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From: San Antonio, USA
C204 C63 P31, A205 C63, C204 C63 507 Edition, C117 CLA 45
No it's a pressure release valve from Weistec. It will add a recirculation route away from your turbo to help with compressor surge. I added it after I got the code for the efficiency of the charge air cooler is not sufficient. I also did a full coolant service. I recommend adding the valve to help with the pressure and checking for any trapped air in your system. Can you see your adaptations on your scanner?
Last edited by AMGMoterWorks; May 19, 2025 at 05:45 PM.
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No it's a pressure release valve from Weistec. It will add a recirculation route away from your turbo to help with compressor surge. I added it after I got the code for the efficiency of the charge air cooler is not sufficient. I also did a full coolant service. I recommend adding the valve to help with the pressure and checking for any trapped air in your system. Can you see your adaptations on your scanner?
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Newbie
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From: San Antonio, USA
C204 C63 P31, A205 C63, C204 C63 507 Edition, C117 CLA 45
Your ECU could be throwing the car into limp mode because the adaptations are off due to fuel system electrical issues. Maybe time to replace fuel pumps.
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