2013 Hi there! right had an overboost P0234 on C Class w204
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2013 C250 Coupe
2013 Hi there! right had an overboost P0234 on C Class w204
2013 C250 Coupe. Car goes into limp mode and pops PO234 code. It also uses lots of Gas. use Premium and get 100 miles to half tank. Anyone have any suggestions? Also when in E gear it has very slow pickup.
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Joined: Mar 2025
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2012 C250
Just getting the same code with mine
. What was the fix for your over boost condition ?
Joined: Nov 2016
Posts: 7,847
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Overboost can be caused by a defective wastegate actuator or diverter valve. The actuator is vacuum controlled, so check your vacuum lines. However, I believe our turbos are built to have open position as the default, meaning you should get little to no boost as the exhaust gases bypass the turbine. If the diverter valve is not working correctly, you may have an overboost condition when gears change or upon sudden off-throttle coditions, such as sudden braking.
Are there any other codes? Have you scanned your car with a Mercedes-specific scanner. (Search the forums for "baby scanner" for a discussion.)
Are there any other codes? Have you scanned your car with a Mercedes-specific scanner. (Search the forums for "baby scanner" for a discussion.)
Last edited by JettaRed; Mar 29, 2025 at 08:25 PM.
Newbie
Joined: Mar 2025
Posts: 3
Likes: 0
2012 C250
Overboost can be caused by a defective wastegate actuator or diverter valve. The actuator is vacuum controlled, so check your vacuum lines. However, I believe out turbos are built to have open position as the default, meaning you should get little to no boost as the exhaust gases bypass the turbine. If the diverter valve is not working correctly, you may have an overboost condition when gears change or upon sudden off-throttle coditions, such as sudden braking.
Are there any other codes? Have you scanned your car with a Mercedes-specific scanner. (Search the forums for "baby scanner" for a discussion.)
Are there any other codes? Have you scanned your car with a Mercedes-specific scanner. (Search the forums for "baby scanner" for a discussion.)
When I cleaned the intake manifold I took off the swirl motor off and believe I didn't zero it dout properly. I pull it back off off and Zero it out to the one o'clock position before installing it again. I used brake clean to clean it and realized after that wasn't a good idea so I purchased 3 new Bosch pressure sensors from rockauto.
Took the car out for a drive and it went into lip mode revealing the above codes.
I figure it has something to do with the new sensors. I did a little digging online and found Mercedes has a different part number for each individual sensor, so I am thing they're not interchangeable. Any thoughts ??
Lastly as the car is old I am going to replace the vacuum lines/actuator/seleniod and that three way pressure switch.
Pat
I figure I would
Joined: Nov 2016
Posts: 7,847
Likes: 3,495
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
BlueDriver is OK, but I woiuld not have it as my only scanner. Look for the LAUNCH Creader Elite BENZ for a little more than BlueDriver. Save BlueDriver for any other cars you have.
