CLC180 Kompressor Hunting

[f17ant]

Hi Everyone

My cousins CLC180 Kompressor (2010) hunts on ideal (driving is perfectly fine)
I used to own one years ago and remember reading on the internet that they split the rubber hoses under the air box.

So got the air box out and hoses are fine it has a hard plastic hose instead of the rubber one (not sure if Mercedes changed it at some point)

Anyways diagnostic showing MAF sensor, my cousin got a cheap one on eBay and it still hunts im telling him it’s probably because that cheap Chinese crap new is probably worse than the broken genuine part.

He said he will order a decent part im still pushing him for a genuine part. But other than that is there anything else to check ? I checked all other hoses sprayed a bit of water on them to see if they bubble and nothing. I don’t think it’s the dreaded timing chain stretch because with a little bit of revs 1000 RPM the engine runs smooth and rattle free

Any help will be appreciated

 

[markjay]

The CLC is CL203 and it is based on the W203 and has the M271 engine.

The 'hunting' when idling could very well be the result of a vacuum leak. The hose that usually splits is under the air cleaner box and it's a big job to get to it, are you sure your cousin is looking in the right place?

(BTW, if he does get to it, I suggest that he should also replace the crankcase breather while he's there)

Gummed-up intake throttle valve is another possibility...:

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Other than that, it will require diagnostic using STAR (or ICarsoft/Carly).

 

[f17ant]

The CLC is CL203 and it is based on the W203 and has the M271 engine.

The 'hunting' when idling could very well be the result of a vacuum leak. The hose that usually splits is under the air cleaner box and it's a big job to get to it, are you sure your cousin is looking in the right place?

(BTW, if he does get to it, I suggest that he should also replace the crankcase breather while he's there)

Gummed-up intake throttle valve is another possibility...:

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

Other than that, it will require diagnostic using STAR (or ICarsoft/Carly).

Yes I definitely checked! My cousin doesn’t no what way to hold a screw driver haha.

The air box was tricky to get off and I 100% remember it was a hard plastic pipe not the normal rubber ones you see on the internet on the “how to” videos

I used a diagnostic tool and it’s coming up with MAF sensor but maybe the cheap replacement he got off eBay was just crap (was a Chinese part)

Was just wondering if there was anything else to check

 

[W1ghty]

Yes I definitely checked! My cousin doesn’t no what way to hold a screw driver haha.

The air box was tricky to get off and I 100% remember it was a hard plastic pipe not the normal rubber ones you see on the internet on the “how to” videos

I used a diagnostic tool and it’s coming up with MAF sensor but maybe the cheap replacement he got off eBay was just crap (was a Chinese part)

Was just wondering if there was anything else to check

There is another hose that cracks/leaks , it’s below the manifold which is below the airbox .

 

[W1ghty]

Is this the hose that you are saying is hard plastic below the airbox

 

[f17ant]

There is another hose that cracks/leaks , it’s below the manifold which is below the airbox .

Manifold off job ? Or can be done underneath the car ?

 

[f17ant]

Is this the hose that you are saying is hard plastic below the airbox
View attachment 133797

Correct that’s all the ones I see online but his is a more hard plastic pipe with no marks on it

 

[W1ghty]

Manifold off job ? Or can be done underneath the car ?

I think it’s manifold off , so where I did my one below the airbox I wasn’t tempted to go further . That’s a bit above my experience, especially I was only doing the top one as a just in case .

 

[f17ant]

I think it’s manifold off , so where I did my one below the airbox I wasn’t tempted to go further . That’s a bit above my experience, especially I was only doing the top one as a just in case .

Makes sense looks like someone has changed that pipe in the past and didn’t do the one under manifold