Sudden loss of power + smoke coming out of exhaust

[MBnewbie123]

Hi,

I own a W204, if you need any more details about my car after reading this, please let me know.

Regularly, smoke is coming out of the exhaust and when I press the throttle down hard a lot of smoke comes out and it is black in colour.

The car seems to run okay, but then suddenly it will go into a mode where the ESP is deactivated and there is a sudden and drastic loss of power. It seems to happen when the car is being driven on motorways or dual-carriageways. I have not noticed the problem happen on B roads (I am in the UK) and the car is being driven at speeds similar to the speeds it is driven at on the motorway or dual-carriageway. I am able to maintain good speed in the car, but it is as if all torque has gone – maybe that is not the correct description.

On short drives where the average is about 20 mph, the car is fine – except for the smoke problem.

I brought it to a reputable Mercedes-Benz garage, and it was fixed, but the problem has come back.

I bought an OBD reader it showed the following fault codes:


POI 23 - Powertrain

Throttle/Pedal Position Sensor/Switch A Circuit

High Input

P2263 - powertrain

Turbo/Super Charger Boost System Performance

P2506 - powertrain

1) ECM/PCM power Input Signal Range/

Performance

P203A - Powertrain

P207C - Powertrain

P22E3 - Powertrain

P23E2 - Powertrain

P2638 - Powertrain



P0089 - Powertrain

P0087 – Powertrain

P0088 - Powertrain

Suction control valve stuck

P0340 - powertrain

Camshaft Position Sensor "A" Circuit (Bank 1 or

Single Sensor)

U0103 - Network

P0183 - Powertrain

Fuel Temperature Sensor A Circuit High Input

P200B - Powertrain

P2054 - Powertrain

Reductant Injector Circuit Low bank Unit 2

P210A - Powertrain

P22E2 – Powertrain

P22E7 - Powertrain

Torque Management Feedback Signal A Range/Performance

--------------------------------------------------------------------------------

I appreciate that is a lot of information, but I want to work out the problem is, bring it to a mechanic, and get it fixed. Given the car starts, and for the most drives fine – I cannot help but think there is an easy solution to this. The smoke coming out the back may be unassociated, so I would appreciate it if someone could tell me how I could stop that.

Thanks in advance.

 

[oigle]

Black smoke is caused by one thing only....too much fuel for the amount of air being ingested. Can be caused by a number of things. Split boost hose is one. Failed boost controller is another. There are no doubt others but those two are simple to check.

 

[Larkone]

If a 'reputable MB garage' fixed it before why not go back and tell them the problem has returned

 

[MBnewbie123]

Black smoke is caused by one thing only....too much fuel for the amount of air being ingested. Can be caused by a number of things. Split boost hose is one. Failed boost controller is another. There are no doubt others but those two are simple to check.

Thank you for the info. Based on the fault codes I inserted above, can you see any that might be indicating what is causing the smoke?

 

[MBnewbie123]

If a 'reputable MB garage' fixed it before why not go back and tell them the problem has returned

I would but they are very far away, and in a rural area. The guy has a swarm of MBs around him and apparently is great with them, but it is an awful inconvenience if I leave the car with him. £80 in taxis. I brought it to him thinking the problem would be solved. He assured me it was. Then it came back. I cannot help. but think it is a sensor or something trivial as the car drives fine... apart from the occasional sudden loss of power!

 

[Taffy7hfa]

I doubt it's a sensor, if the ecu is putting the engine into lymp mode it likely has a genuine fault probably fuel system related, as Oigle has said it sounds like overfuelling but that could be caused by many many different things, your generic code reader won't help much it needs diagnosing using Star or similar by someone who knows what they are doing. Guesswork is pointless.

 

[mioba]

if you got a code reader and dont know how to use it - bin it.

let the mechanic do his job.

We could tell you many things, it could be a-z........ an experienced MB indy knows how to decipher codes, with live data and find the problem.

 

[rf065]

You say the car has a 2 litre engine, but I cannot see any 2008 models with an engine that size, so I'm assuming it's the 2.1 diesel?
If so, first thing I'd look for is a split in the intercooler hose, Difficult to spot sometimes when not under boost pressure, but a good starting point.

 

[alexanderfoti]

The most likely does seem to be boost leak, intermittent turbo issues going on the codes and symptoms. Faster roads put the car into a higher boost level so the ecu notices at this time.