c270 rail pressure sensor and more

[housewinnie]

Hi guys, 2002 c270 estate 107000 miles done, broke down the other day the cars revs started chasing up and down between 500 and a 1000 revs then it died, got it going again but stopped 10 miles up the road. el. power control EPC was the error displayed on dash.

eventually got the car recovered home and it started again and all the faults were cleared, drives ok at the moment but smells a bit inside the car of diesel.

Have removed the plastic engine cover and had a look and it seems a little oily or diesely around a black round plastic part near the front on top of the engine just forward from the place where you fill up with oil.

It has also been into Mercedes and the faults as below came up.

Rail pressure sensor faulty
Rail pressure regulator stuck in closed position
Low pressure diesel pipes leaking

You can imagine what they quoted to fix and not sure if the car is worth it.

Can any of the above be done by myself, am not too bad at diy mechanics if i know where the fault is....

cheers in advance.

Also some of the turbo pipes are breaking up but thought i would start at the top and work my way down...

Help

 

[toby1]

What did they quote to fix? My imagination is lacking

 

[housewinnie]

about a grand

 

[housewinnie]

have investigated further and it seems the part i was trying to explain which seems a bit diesly and oily is the oil separator. could this cause a problem?

 

[Steve@Avantgarde]

The fault codes you have stored are standard for low fuel pressure. This can be caused by a few things but the fact you are getting an EPC visit workshop on the dash would say to me you have 1 or more injectors with high leak off/worn nozzles/high quantity correction. It would also explain your poor idle. I would have thought the dealer would have checked the quantity correction value on STAR and recommended a leak off test....

Anyway, your fault is likely an injector or 2 failing.

 

[housewinnie]

thank you for the reply, would that explain the smell of diesel inside the car when driving? cheers

 

[st4]

thank you for the reply, would that explain the smell of diesel inside the car when driving? cheers

Yes. Leaking injectors will do this. The issue is known as black death. A grand to fix I don't know if that's a good price but the car will be worth a fair bit more than double that cost so it's viable.

 

[housewinnie]

update and a little more help please

Hi again guys have had the engine cover off today and started the car and found a nice steady drip of diesel coming from what at the moment seems like the fuel line under the high pressure pump...

My question to you all is if i have diesel leaking from this fuel line would this be enough for the engine management to shut the car down?

Also my main dealer have said i have a faulty rail pressure sensor which i can find but also a rail pressure regulator which is stuck in closed position.

Where abouts is the rail pressure regulator please..

thank you so much in advance...

 

[tony jr]

It could be the seals on the high pressure pump that are leaking

 

[mersum1es]

Hi again guys have had the engine cover off today and started the car and found a nice steady drip of diesel coming from what at the moment seems like the fuel line under the high pressure pump...

My question to you all is if i have diesel leaking from this fuel line would this be enough for the engine management to shut the car down?
..

Yep, that happens pretty often what I've read (hit yesterday in my W210 )... leak can be coming either the low pressure lines o-rings, or below the pump flange. Normally the pump leak is worse when cold engine. I was amazed how much it can leak without having any other usual reported symptoms like starting problems and shut down when full throttle. I bought repair set of seals today (about 25€), going to change them during the weekend...

regulator is end part of the rail I assume (another end that pressure sensor )

 

[housewinnie]

Last question for now, and all this input is really appreciated, is there an easy way to see if the leak is from the fuel line under the high pressure pump or from the pump itself, as it only leaks when the engine is running and am getting a little too close to the spinning belts.

OK one final final question is it straight forward changing the fuel lines with the pump still on the engine?

thank you all so much once again

 

[tony jr]

probably best to clean around the high pressure pump and fuel ines with some engine degreaser let it dry then start it up and see where the leak is coming from

 

[mersum1es]

mine is also leaking from same(?) place, but I was not able to see exact place (too much leak), so I bought also o-rings of the low pressure lines.

 

[Steve@Avantgarde]

I have never had a leaking fuel line cause ESP visit workshop as although it leaks, it cant leak fast enough to drop the rail pressure to below 150bar causing the EPC warning and cutting the engine. There isnt enough pressure on that side of the system to cause it. The issue will be injector related im sure.

 

[tony jr]

Last question for now, and all this input is really appreciated, is there an easy way to see if the leak is from the fuel line under the high pressure pump or from the pump itself, as it only leaks when the engine is running and am getting a little too close to the spinning belts.

OK one final final question is it straight forward changing the fuel lines with the pump still on the engine?

thank you all so much once again

Have you had time to look at this yet?

 

[housewinnie]

New pressure regulator valve and sender unit plus new fuel lines...hopefully this has fixed it....

 

[Speed creek]

Can any one please help mine starts up after about 5mins of turning over put new pump on low pressure new filter still the same if u give a kick down the epc comes on cuts out then try start it all over again can some one help plz

 

[Westheath]

Can any one please help mine starts up after about 5mins of turning over put new pump on low pressure new filter still the same if u give a kick down the epc comes on cuts out then try start it all over again can some one help plz

Might be better to start a new thread............

But do an injector leak off test first, you could have low rail pressure due to bad injector/s
Or
Bad fuel pipe O ring seals allowing air into the system.

Edit: yours is a 2003 so probably don't have the O ring problem.














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