Juan Reyes

Hi everyone,

I have a 2015 C300 sedan base, when I am driving and I give the gas a nice push there is a kazoo like sound that comes out. I have recorded a video and was hoping someone knows what is causing this! Thanks in advance

LINK:

Gazwould

Sounds like a boost pipe split , but a 300 is NA ?

Juan Reyes

Yes, here in NA. Took my c300 for a ~120 mile drive, had it on sport+ and everything was fine. Once I get to my destination it started making this noise. Only when I’m accelerating pretty fast, does not make noise if I’m accelerating moderately

zibby43

W205 C300 has a 2.0L 4-cylinder turbocharged motor.

zibby43

Take it to the dealer, especially if you have any warranty or extended warranty left.

BayAreaAMG

Yup what the other person said. That car has a turbo right? That definitely sounds like a boost leak coming from intercooler piping somewhere. Probably a clamp on one of the piping got loose and it leaks since it's under pressure while accelerating. That's what it sounded like on my last car.. Kinda sounds like a choo choo train 😄.

A boost leak test will need to be done.

irondad

NA in his question means Naturally Aspirated, i.e. non-turbo. Your engine is turbocharged. There's a leak and you're hearing that noise when the turbo spools up and increases the volume of air coming through.

GringoBling

boost leak, check the plastic tube that connects the air filter housing to the turbo

Juan Reyes

thanks I'm going to take it to get it looked at this weekend, hopefully its nothing crazy

Juan Reyes

thanks zibby, I'm taking it to get it checked out, I do have bumper to bumper ext. warranty so hopefully that'll do something lol

Juan Reyes

Thanks for the explanation irondad, I thought he was asking if I was in America lol

Juan Reyes

I'm taking it to get it looked at. Is this something that can be done at home though? Not really into fixing cars, most I've done is change the cabin air filter and clean the evaporator coil lol

BayAreaAMG

The boost leak would be coming from one of the the "charge pipes", either going from the turbo to intercooler, or from intercooler to throttle body on the intake manifold of the engine. I suppose it could be possible that a vacuum/boost hose is also off but then I am confident that you would get a CEL for that.. So any clamp in-between the turbo and throttle body would be the suspected areas to look at first. See if any are noticeably loose - but keep in mind they can appear tight but still leak once turbo boost pressurizes the system... Also see if a pipe does not look like it is connected completely flush to the turbo, intercooler or throttle body which could be a sign of the leak as it could have pushed it out of place a bit when it leaked..

If none of the above, perhaps one of the pipes or the intercooler itself has cracked and has a leak, In which case you need to have it replaced.

If you take it into a shop they will likely just do a boost leak test to pinpoint where the leak is. Which they will disconnect the air intake and connect an air compressor setup to the turbo, and slowly pressurize it to hear where it is leaking from.

EDIT: but honestly, if this is out of your comfort zone to troubleshoot it would be best to just take it in.

Juan Reyes

thanks, I took it to go get looked at, told him what you guys told me, showed him the video. He came back after 10 min of looking at my car, it was a clamp like you said. Didn’t even charge me. Thank you!!