'05 C220 Black Smoke and Powerless

[JSeaman]

Hi all,

We just bought a 2005 220 CDI which we were going to use as a tow car but it's struggling on power, it just about managed to tow a caravan but felt like the box was slipping on pull off and generally sluggish. I also discovered huge plumes of black smoke when you give it more than half throttle (proper James Bond style smokescreen!)

So it's obviously firing out a load of diesel which isn't being burnt, I'm after likely suspects and any inside information. I've had a quick look tonight and changed the air filter, no sign of the 'black death' so I was going to move onto the EGR next to see how it looks. After that I will check induction pipework and then I'll be needing some ideas!

No sign of any warning lights and it generally drives OK (idles fine etc) but obviously has an issue. Any thoughts welcomed

James

 

[AMGeed]

Check all the boost hoses for leaks and splits. Common cause where there is lots of black smoke.

 

[Steve@Avantgarde]

Find an independent with STAR, check the fault codes first and then proceed from there.

 

[Taffy7hfa]

Alternatively, assuming the engine has been properly serviced and is generally in good order, you could try a bottle of Redex and a 2 hour blast up the motorway @ 3,000rpm, common rail diesel engines like nothing better than being worked really hard for prolonged periods.

 

[om613]

Alternatively, assuming the engine has been properly serviced and is generally in good order, you could try a bottle of Redex and a 2 hour blast up the motorway @ 3,000rpm, common rail diesel engines like nothing better than being worked really hard for prolonged periods.

He's got a fault with black smoke. Redex won't fix it.

 

[Taffy7hfa]

It might if he has dirty injectors.

 

[Steve@Avantgarde]

It might if he has dirty injectors.

No such thing....

 

[Taffy7hfa]

You better tell this lot then, I'm sure they will be very disappointed.

 

[umblecumbuz]

Wow! I've never come across a manufacturer who claims his product will fix a problem that doesn't really exist before!
Snake oil.

On a more serious note, I wonder if your autobox is behaving as it should? You suggest that it might be playing up. Does it change up and down normally? When you get the codes read - the obvious way forward before throwing money and parts at the car - get the fluid level in the box checked out at the same time.

 

[Steve@Avantgarde]

You know what, I have never fixed a car yet by throwing additives at it. I have actually fixed a whole load of cars by understanding the faults and seeking the cure through correct diagnosis...

 

[Westheath]

Hi all,

We just bought a 2005 220 CDI

Any thoughts welcomed

James

Take it back

 

[JSeaman]

Hi guys, sorry for the delay coming back - finally got half an hour on the car this evening and took the air inlet housing off, it was mucky but not too bad:

EGR

• JSeaman
• Nov 6, 2017

I'll do the other end tomorrow with the valve itself if I get time

It's had a few good runs now and is no better

I found quite a bit of oily crud in the intake manifold but it's not looking awful

The auto box seems to be changing as it should and manually it's no better

No codes (that would be too easy wouldn't it!) with an OBD reader

I'll skip over the 'take it back' and 'redex' suggestions

Anyone got any more thoughts, I'm going for induction piping once I've got the actual EGR off

 

[LostKiwi]

What are you using to read codes?

 

[JSeaman]

Just an OBDII, I know STAR does more but there are no basic errors. I'm hoping the valve reveals more of the black stuff but I doubt I'm that lucky

 

[Steve@Avantgarde]

Thats an electric EGR, so if it had any trouble opening or closing it would have told you. A bit of a pointless exercise to be honest and I feel you're rather clutching at straws.

 

[Westheath]

Well that's kinda what forums are for really,
some poor sods bought a car with a fault and can't/won't back it,
so some good old straw clutching on a forum in hope of a result
before having to fork out more hard earned dosh

So........Firstly.

Black smoke and Low power = imbalance in the air to fuel ratio - too much fuel to not enough air.
Check for boost hose splits, loose boost hose connections, split/worn boost hose sealing rings,
any thing on the inter-cooler split or cracked.
Make sure the charge pressure system isn't leaking basically.

If the systems airtight then move on to injector and fuel system testing.

And this is best done on MB Star

 

[JSeaman]

Some rather disappointing responses but thanks to those actually trying to contribute

I've had a wander around the intake piping now and there is no sign of a split but I really need to take it all apart and flex them a bit to check properly. I noticed when pulling ot the inlet manifold pipe there was more oil than I wanted to see so turbo seals are a bit suspect

The EGR was a bit coked up so I cleaned that out late last night and my wife will give it a try today, it wasn't so bad that I think it's the problem.

There is another little nugget of information, the temperature sits between 60 and 80 so the stat is getting attacked next as it's a quick fix.

I'm swaying towards turbo and cats at the moment but if you have any fuel-side ideas I can look for I'm all ears

 

[umblecumbuz]

If the 'stat is not rock solid at 85, then it needs changing. This will improve consumption and engine efficiency, but it isn't the main cause of your problem.

A generic OBD2 reader will not give you the full picture on a Merc. Either upgrade to a Merc dedicated scanner (iCarsoft make several) or get it properly diagnosed with Star.

It's satisfying to get to know your car by servicing/inspecting components as you are doing, but for a proper diagnosis and health check, Star is the way forward. Presumably you've ruled out going back to the Dealer (if it wasn't a private purchase)?

You've knocked the forum a bit here, but analysing the replies you've received, you'll agree that they've all pointed you in the right direction, and potentially got you further than you would have got on your own.

 

[John Laidlaw]

I’m with the others, needs some useful diagnostic with the right kit firstly.
Secondly 12+ year old hoses can unfortunately delaminate and have fine splits which are difficult to see, so double check those

 

[Steve@Avantgarde]

Hoses that are old can also collapse on throttle causing the engine to choke.

The op says he is disappointed with responses, but I am not sure what answer he was hoping to get?

As i have said on other threads and will say here, you can't guess at fixing cars. If you have a fault, check the codes, obtain the information and follow the procedure of diagnostics that will lead you to the cure. Simply throwing bits at it or taking things to pieces will only cost more in the long run.

However I do agree that if the Tstat isn't getting to operating temperature, then that should be replaced ASAP, but it won't be the cause of the smoking issue.