CLS 250 cdi 2013 turbo pipe hissing noise after replacement

[idbb1]

Hi, first post on the forum. Thanks in advance for any replies.

My passenger's side turbo pipe went on the CLS and I've decided to replace it myself.

I changed it alright and both clips hold, but the car is hissing air when driven. It's fine when I just rev it, but the hissing starts when I drive it. Also, the car doesn't accelerate like it should.

I took the pipe out, made sure the o rings sit inside the hose properly and that the hose catches onto the plastic pipe nice and deep but still the same thing.

Any idea what am I doing wrong?

Many thanks,

Tom

 

[BlackC55]

Do you have another split pipe?

Are you sure the new pipe is fully clipped in?

 

[idbb1]

I’m taking it off today to have a look and post an update on here later today. If anything, I’ll have the old pipe as it was the oring that gave on the first one so I can just replace the oring and fit the old pipe to see if it’s any different.

And yeah i need to make sure it sits properly cos the first time I’ve done it it came out when I drove off :/

 

[idbb1]

There’s progress. I took it off, cleaned a tiny bit of oil that was around the clips, put it back on and it seems alright now although there’s still a bit of hissing coming out from that area. Not sure if it’s the pipe or the turbo itself and I’m positive that hissing noise wasn’t there before. The car accelerates normal now.

 

[Jigglyjohnson]

I'd say the clip isnt holding correctly. Or it isnt seating correctly causing the hissing under boost pressure

 

[idbb1]

I’m about to give up on thing. I think if it wasn’t sitting correctly it would have come off cos the clip wouldn’t have caught the plastic wall that’s meant to hold it in place. And I can’t push it any further. It’s actually pretty straight forward to attach it I think.

so, I thought it could be the pipe as it was from eBay. I got a new one from Mercedes, put it in today and it’s the same thing. Still hissing but the car is going.

What the heck am I doing wrong with this thing? It’s so frustrating.
Thanks

I'd say the clip isnt holding correctly. Or it isnt seating correctly causing the hissing under boost pressure

 

[Tonygw]

Do you have full power? There are two hose's I believe one each side of the intercooler, you sure the other one isn't split or failing also?

Is it a loud hiss then? it could be something else causing the noise?

 

[idbb1]

Do you have full power? There are two hose's I believe one each side of the intercooler, you sure the other one isn't split or failing also?

Is it a loud hiss then? it could be something else causing the noise?

Thanks for replying. It’s definitely not the other pipe. The car has full power and engine light doesn’t come on. Hissing is quite loud.

I found a bit of oil leak from the area the hissing is coming from though, but couldn’t see where exactly. Any idea what these pipes are? They’re on the passenger side closer to the middle of the car right behind the engine.

maybe it’s worth saying the hissing only starts when I drive the car. When I rev it when stationary it’s all good. Wouldn’t the pipe make hissing noise when revved too?

thanks for your help

 

[idbb1]

 

[Tonygw]

Sorry not sure what the pipes are, maybe breather pipes to do with the emmisions maybe? Just a thought, the hissing isn't a brake disc scraping that sounds like a hiss is it? They can sound similar. It's a bit odd it only does it while your driving.. can you pinpoint which side it's coming from?

 

[Stratman]

Put some washing up liquid and water around the joints, that should reveal any leaks.

 

[idbb1]

Sorry not sure what the pipes are, maybe breather pipes to do with the emmisions maybe? Just a thought, the hissing isn't a brake disc scraping that sounds like a hiss is it? They can sound similar. It's a bit odd it only does it while your driving.. can you pinpoint which side it's coming from?

Hissing is coming from the same side the pipe was replaced at (passenger side). And now only when I boot it, it’s like a steam engine that loud, but it’s not there when accelerating slowly. You can almost feel the hiss inside the cabin where the glovebox is when accelerating fast it’s so strange.

thanks for the tip about washing up liquid. I used brake cleaner and will see in a couple of days where the leak is coming from.

 

[idbb1]

I shot a quick video with the hissing sound, it's there every time the car accelerates.

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[Muckypaps]

It won't hiss when stationary as no boost pressure generated when stood.

 

[BlackC55]

On the video I can't hear a loud hissing noise.

Get a MB specialist to have look and a take it for a drive. They will have experienced many.

 

[CarFan79]

As it's CLS250 I'd imagine it's a OM651 engine and these suffer from inlet manifolds leaking from a snapped and/or loose bolts.

 

[idbb1]

As it's CLS250 I'd imagine it's a OM651 engine and these suffer from inlet manifolds leaking from a snapped and/or loose bolts.

Thanks for this, I’ll have that checked out. Just curious, is it a matter of replacing/tightening the bolts or is it a bigger job such as replacing the gasket since it’s been leaking etc?

 

[CarFan79]

Thanks for this, I’ll have that checked out. Just curious, is it a matter of replacing/tightening the bolts or is it a bigger job such as replacing the gasket since it’s been leaking etc?

Best having the intake system pressure tested or checked with a smoke pro machine to check for leaks from the manifold.

I've mostly done them on the commercials. If the bolt has snapped it will need drilled out of the cylinder head and a new manifold, water connection and various seals/gaskets. If just loose you could possibly get away with tightening and only a few seals/gaskets. It's quite labour intensive as lots of stripping involved.

 

[idbb1]

Best having the intake system pressure tested or checked with a smoke pro machine to check for leaks from the manifold.

I've mostly done them on the commercials. If the bolt has snapped it will need drilled out of the cylinder head and a new manifold, water connection and various seals/gaskets. If just loose you could possibly get away with tightening and only a few seals/gaskets. It's quite labour intensive as lots of stripping involved.

Thanks so much mate

 

[CarFan79]

Hopefully it's not the manifold and something simple instead.