2014 GL450 V8 Turbo Underboost -P0299
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2014 Gl 450
2014 GL450 V8 Turbo Underboost -P0299
Can someone please help me diagnose the issue on my 2014 GL 450 showing engine light with P0299. It shows vacuum leak on solenoid in the engine reader. I got it fixed from the european mechanic, he told me it was SOLENOID PRESSURE VALVE and changed it but the issue still exists. Did someone else have the same issue?
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From: New Jersey
GL 450
I do not have direct experience, but if the code is a vacuum leak, I would get a smoke test done. A cheap way to rule out a leak, which can manifest in many adverse ways and lead you on a parts replacement journey.
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From: Conway, AR
2015 GL550
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mgLipGD
https://www.ebay.com/itm/31451404790...mis&media=COPY
1 of these $50 but seems to be hard to find
https://www.autohausaz.com/pn/PB-0001531800
still waiting on parts but also read to check air filters. I checked and both sides had tons of stuff in there, more than usual. So cleaned out will order some AFE Pro dry filters I use my G and E AMG models. Why I never put butter filters in there 🤷🏻♂️. Anyway cleared code and drove much better today. Time will tell and I will have the parts on standby, as I want to see now if it really was the filters restoring air flow.
Junior Member
Joined: Sep 2007
Posts: 32
Likes: 5
From: Conway, AR
2015 GL550
2 of these $25
https://www.ebay.com/itm/31451404790...mis&media=COPY
1 of these $50 but seems to be hard to find
https://www.autohausaz.com/pn/PB-0001531800
still waiting on parts but also read to check air filters. I checked and both sides had tons of stuff in there, more than usual. So cleaned out will order some AFE Pro dry filters I use my G and E AMG models. Why I never put butter filters in there 🤷🏻♂️. Anyway cleared code and drove much better today. Time will tell and I will have the parts on standby, as I want to see now if it really was the filters restoring air flow.
https://www.ebay.com/itm/31451404790...mis&media=COPY
1 of these $50 but seems to be hard to find
https://www.autohausaz.com/pn/PB-0001531800
still waiting on parts but also read to check air filters. I checked and both sides had tons of stuff in there, more than usual. So cleaned out will order some AFE Pro dry filters I use my G and E AMG models. Why I never put butter filters in there 🤷🏻♂️. Anyway cleared code and drove much better today. Time will tell and I will have the parts on standby, as I want to see now if it really was the filters restoring air flow.
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2014 Gl 450
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From: Usa
mgLipGD
Hope that helps as those are easy cheap options to check if the turbos seem to not be leaking.
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2014 Gl 450
I went to replace the boost solenoid under the engine cover but she I was removing one of the rubber lines it easily tore. Replaced solenoid and temp super glued the rubber line were torn. Issues resolved but I suspect it was really just a small tear in the rubber connector that when warm would often cause the code.
Hope that helps as those are easy cheap options to check if the turbos seem to not be leaking.
Hope that helps as those are easy cheap options to check if the turbos seem to not be leaking.
