CLS (E class) 320cdi P0087 and P0193 ???

[Mr Hatt]

Sooo what I thought was perhaps an in tank pump issue is now debunked and that end is doing what it should, the car broke down as if it was running out of fuel and was recovered, it will actually start now having scrubbed fault code but is in a limp mode, I had P0087 fuel pressure system too low when it broke down and it has now returned with its mate P0193 Fuel rail pressure sensor high output ??
This would appear to suggest the fuel pressure in the rails is fluctuating ?
I service this regularly and the diesel filter was done in June using genuine, having checked the tank, its fine and if I loosen filter fuel outlet out pipe clip just a little it is spraying out so I have put the idea of low pressure system issue to bed for now although I was unable to check exact pressure.
Next culprit on my list will be fuel quantity control valve on high pressure pump moving on to fuel rail pressure sensor to see if its reading wrong, I do have a complete working 2009 E320cdi to swap parts with if they are correct part numbers but do not have Star just I carsoft and dare not take it out on road at moment in case I end up on grass verge again.
Any thoughts or experiences from any of you who may have had similar issues would really be appreciated, thanks in advance Steve

 

[mioba]

What code reader are you using.

 

[Larkone]

The one he mentions in his post - 'do not have Star just I carsoft'

Can you read the live values for pressure using your I-carsoft? Might help point to the issue, but failing that STAR.

 

[bembo449]

spill test injectors is what I would do

 

[Mr Hatt]

What code reader are you using.

thanks for reply I have I Carsoft which is pretty basic

 

[Mr Hatt]

The one he mentions in his post - 'do not have Star just I carsoft'

Can you read the live values for pressure using your I-carsoft? Might help point to the issue, but failing that STAR.

Not sure thats possible with I carsoft but will look into it thanks for the reply, steve

 

[Mr Hatt]

spill test injectors is what I would do

Hi bembo I have considered the injectors as a next step after pressure sensor and quantity control valve, as the codes show nothing from injectors, which I would have expected, I will move in that direction if I need to but you are all right about needing Star, I could really do with knowing someone local with one or picking one up for myself, I have looked at the various models available second hand but there are lots of versions and i am not sure which to go for on my 2006 car, any advice would be appreciated regards Steve

 

[bembo449]

ive never seen any injectors show a fault on a scan tool and hence why I always spill test them , the leak off is usually a tiny bearing and spring not electronic so doesn't show as a fault

 

[Mr Hatt]

ive never seen any injectors show a fault on a scan tool and hence why I always spill test them , the leak off is usually a tiny bearing and spring not electronic so doesn't show as a fault

Thanks Bembo as I said that was on my list next but the day took a quite a different turn, I cleared the codes and tried a start, still nothing and high pressure in rail codes came back on so was about to pull the sensors when I found that that they were all connected via the Brabus box that was on it when I bought it, I get about 45mpg so it seems to have done a good job but if I am to get correct undiluted readings from the MB system I thought it best to completely disconnect it, had to pull a few parts off to get all the connections but having reassembled it and turned the key it started perfectly and engine management light was out, did not think for a min that it might be cured because I did have it running yesterday but it cut out over 3000 revs so let it warm up cleared old codes and re scanned, nothing! no issues, gave it a boot full and still nothing, take it to red line then felt confident enough to road test and all is well, no problems, no codes and pulls right up through the rev range again.
I can only assume that the Brabus box went bad but after the two years of good service it certainly picked its time well, christmas eve in the driving rain and cold, I have now added recovery to my basic RAC cover but hopefully will not need it, kind regards Steve

 

[bembo449]

Ok steve , thats a bit unlucky but i reckon id have a lower powered car that works perfectly than one the other way round

 

[Mr Hatt]

Ok steve , thats a bit unlucky but i reckon id have a lower powered car that works perfectly than one the other way round

Thats the irony, I dont drive fast and only left it on in case the claim of saving fuel is real

 

[mattkh]

Thats the irony, I dont drive fast and only left it on in case the claim of saving fuel is real

The Brabus box probably developed a faulty earth connection.

 

[Mr Hatt]

The Brabus box probably developed a faulty earth connection.

I did check that Mat and it must have been internally because it was bolted down solid in a dry position, although its branded Brabus I guess everything today has some Chinese content that lets it down at some point, thats perhaps why I am drawn to old Mercs with proper German tech and components that just work! kind regards Steve

 

[mattkh]

I did check that Mat and it must have been internally because it was bolted down solid in a dry position, Steve

In that case, the heat dissipation paste deterioration may have contributed.