Both turbochargers replaced!
01-25-2023, 07:20 PM
#1
Both turbochargers replaced!
Hi folks,
First post here but wanted to relate a maintenance story with everyone since I think its not very common.
2017 GLS450.
Noticed over the past 6 months some sluggishness on acceleration but dismissed it to being an old car (I have 115,000 miles now). The engine data screen showed I was maxing out at about 250tq and 250hp. Decided to take it into the $tealer because I am still under the CPO extended warranty (unlimited mileage!). Diagnostics found a P0299 underboost code. They did further diagnostics and found at the wastegates of both turbos. Both sides! There was a delay in obtaining parts due to the supply chain shortage, and it took 3 weeks for both turbos to be replaced. Not too bad after hearing about how some wait months for a bracket or trim piece while their car is held hostage by the dealer.
Am wondering if any other X166 GLS450 here has had their turbo replaced. They told me it was fatique from the wastegate actuator. There was nothing on the smoke test and all the ducting was intact. Always oil changes every 5000 miles with Mobil One, so its not lack of oil changes jamming up the oil lines.
So happy to have my car back and it definitely has the old zip I remember when it was newer.
First post here but wanted to relate a maintenance story with everyone since I think its not very common.
2017 GLS450.
Noticed over the past 6 months some sluggishness on acceleration but dismissed it to being an old car (I have 115,000 miles now). The engine data screen showed I was maxing out at about 250tq and 250hp. Decided to take it into the $tealer because I am still under the CPO extended warranty (unlimited mileage!). Diagnostics found a P0299 underboost code. They did further diagnostics and found at the wastegates of both turbos. Both sides! There was a delay in obtaining parts due to the supply chain shortage, and it took 3 weeks for both turbos to be replaced. Not too bad after hearing about how some wait months for a bracket or trim piece while their car is held hostage by the dealer.
Am wondering if any other X166 GLS450 here has had their turbo replaced. They told me it was fatique from the wastegate actuator. There was nothing on the smoke test and all the ducting was intact. Always oil changes every 5000 miles with Mobil One, so its not lack of oil changes jamming up the oil lines.
So happy to have my car back and it definitely has the old zip I remember when it was newer.
01-26-2023, 03:52 PM
#2
Have a similar problem. 2017 GLS450 P0299 Code Low boost.
Found the bypass actuators were oscillating and not fulling engaging.
Checked the vacuum on both actuators - drivers side was leaking, and passenger side was ok.
Plugged the vacuum on the driver side and run the passenger side directly off vacuum with one way vacuum valve.
Adjusted the driver side actuator to be constantly engaged.
Still reports low boost on turbo 1 (not sure which side is turbo 1) - but performance seems to be back where it should be.
Currently have 319+k on it.
Found the bypass actuators were oscillating and not fulling engaging.
Checked the vacuum on both actuators - drivers side was leaking, and passenger side was ok.
Plugged the vacuum on the driver side and run the passenger side directly off vacuum with one way vacuum valve.
Adjusted the driver side actuator to be constantly engaged.
Still reports low boost on turbo 1 (not sure which side is turbo 1) - but performance seems to be back where it should be.
Currently have 319+k on it.
01-26-2023, 04:02 PM
#3
Have a similar problem. 2017 GLS450 P0299 Code Low boost.
Found the bypass actuators were oscillating and not fulling engaging.
Checked the vacuum on both actuators - drivers side was leaking, and passenger side was ok.
Plugged the vacuum on the driver side and run the passenger side directly off vacuum with one way vacuum valve.
Adjusted the driver side actuator to be constantly engaged.
Still reports low boost on turbo 1 (not sure which side is turbo 1) - but performance seems to be back where it should be.
Currently have 319+k on it.
Found the bypass actuators were oscillating and not fulling engaging.
Checked the vacuum on both actuators - drivers side was leaking, and passenger side was ok.
Plugged the vacuum on the driver side and run the passenger side directly off vacuum with one way vacuum valve.
Adjusted the driver side actuator to be constantly engaged.
Still reports low boost on turbo 1 (not sure which side is turbo 1) - but performance seems to be back where it should be.
Currently have 319+k on it.
01-29-2023, 08:01 PM
#5
No idea. I found the dealership service experience rather middling. They did not explain anything and provided little updates until I really prodded them, and even so thy just made up various explainations that might fool someone who didn't know anything about cars, but not to someone who really wanted to know what was found and fixed. The parts are around $4000-5000 retail, and labor rate is $288 an hour so you can probably bet this may have been a five figure job.
