P0299 - turbo underboost resolved
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Junior Member
Joined: Mar 2010
Posts: 57
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Silver C63 2009
P0299 - turbo underboost resolved
Had this CEL code turn on once in July 2019 and once again yesterday in my 2015 GLA45. Lost major power accelerating. Both times it started after filling up with “91 octane,” (2019 incident was from a Mobil station and yesterday from a Chevron station). It was resolved with draining the gas tank and adding 91 octane from another gas station. The CEL automatically turns off. Hope this helps anyone else in the future.
Member
Joined: Oct 2019
Posts: 100
Likes: 5
From: TAMPA
GLA45 mit optionz; MS6 8 port & stuff
Had this CEL code turn on once in July 2019 and once again yesterday in my 2015 GLA45. Lost major power accelerating. Both times it started after filling up with “91 octane,” (2019 incident was from a Mobil station and yesterday from a Chevron station). It was resolved with draining the gas tank and adding 91 octane from another gas station. The CEL automatically turns off. Hope this helps anyone else in the future.
2 things
1 If you've woken up with a bad tank, get with Ol' Doc methanol. Just a quart or 2 in the tank and troubles are solved, or adsorbed, or something magical.
and 2
Form a stable, monaggyomus relationship with Shell Nitro 93. you'll never wake up with injector rash again
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Joined: Feb 2023
Posts: 1
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Gla 45
Had this CEL code turn on once in July 2019 and once again yesterday in my 2015 GLA45. Lost major power accelerating. Both times it started after filling up with “91 octane,” (2019 incident was from a Mobil station and yesterday from a Chevron station). It was resolved with draining the gas tank and adding 91 octane from another gas station. The CEL automatically turns off. Hope this helps anyone else in the future.
