Code P0128 and P0299
08-02-2023, 04:17 PM
#1
Senior Member
Thread Starter
Code P0128 and P0299
Hello, has anyone had to deal with these codes.The vehicle is a 2014 CLA45. I know they're related to thermostat and turbo waste gate. Car seems to be running okay, temp is okay, acceleration seems normal.
Appreciate any help. TIA
Appreciate any help. TIA
08-04-2023, 07:50 AM
#2
Member
This is probably not the best help but...I have the same year, 2014. On a highway trip, it threw the P0299 code. No limp mode, drove just fine. When I got home, I took apart the air filter, and all the connections to the intake into the turbo from the fresh air side, and disconnected the turbo on the exhaust side. (I am only a wanna be car girl so some of my terms are probably not the technical ones). My intent was to replace the wastegate. Of course, once I received the new wastegate and started seeing how to replace it, I realized it was welded on there, which is above my adventurous car repair attempt threshold.
Feeling defeated, I put it all back together. I did clean out some oil coating the big tube between the air filter box and the turbo, and anything else that seemed icky. and I used a vacuum thing to make sure the wastegate actuator was moving correctly, tried to feel if the wastegate was loose when engaged fully, and tried to visually inspect all the vacuum tubes. Code was cleared because I had disconnected the battery.
Long story short, the code has not come back and it's been over a month of regular driving ( no long highway trips). I don't know if it was some of my highway acceleration that caused it or if some of the small things I did somehow fixed it. I had found some different forums that talked about it and YouTube videos that were diagnosing it, and about replacing the wastegate (but they took the turbo out and sent it to a turbo shop to do it). My mechanic said they just replace the turbo and when I called a local turbo shop, they didn't return my calls. My mechanic also thought it could have been the turbo pressure sensor which I was maybe going to try to replace if the code came back, I think it's less than $150 online and my mechanic would probably charge over that just in labor, although I read threads online where folks did that and it didn't fix the code. But many of them had gone into limp mode, but like you, mine didn't, so it seems our problem is a bit different.
I know this isn't super helpful, but I guess I just hate it when I post something like this and no one really answers, so I wanted to share my story. (I used to have a 2005 C55 and that forum was active and full of DIY guys who taught me so much, I wish this forum was more active!)
Good luck and if you fix it, please share because every time I punch it to accelerate, I worry it's gonna come back.
~M
Feeling defeated, I put it all back together. I did clean out some oil coating the big tube between the air filter box and the turbo, and anything else that seemed icky. and I used a vacuum thing to make sure the wastegate actuator was moving correctly, tried to feel if the wastegate was loose when engaged fully, and tried to visually inspect all the vacuum tubes. Code was cleared because I had disconnected the battery.
Long story short, the code has not come back and it's been over a month of regular driving ( no long highway trips). I don't know if it was some of my highway acceleration that caused it or if some of the small things I did somehow fixed it. I had found some different forums that talked about it and YouTube videos that were diagnosing it, and about replacing the wastegate (but they took the turbo out and sent it to a turbo shop to do it). My mechanic said they just replace the turbo and when I called a local turbo shop, they didn't return my calls. My mechanic also thought it could have been the turbo pressure sensor which I was maybe going to try to replace if the code came back, I think it's less than $150 online and my mechanic would probably charge over that just in labor, although I read threads online where folks did that and it didn't fix the code. But many of them had gone into limp mode, but like you, mine didn't, so it seems our problem is a bit different.
I know this isn't super helpful, but I guess I just hate it when I post something like this and no one really answers, so I wanted to share my story. (I used to have a 2005 C55 and that forum was active and full of DIY guys who taught me so much, I wish this forum was more active!)
Good luck and if you fix it, please share because every time I punch it to accelerate, I worry it's gonna come back.
~M
