P0193 fuel rail pressure sensor circuit a high

[Ml280amg]

Hi all new here. I haven't long purchased my 2007 ml280cdi amg spec.
I bought it not knowing that it had the dreaded oil cooler seals leaking.
After a few quotes from garages to fix it me and a friend of mine decided to give it a go ourselves.
All went well. Time consuming but we got there in the end. Got it started but its lumpy on idle and lacking power while under acceleration. I've got a code reader which reads as title.
Anyone shed any light?

 

[Ml280amg]

Anyone?

 

[mersum1es]

If your (piezo?) injectors had been laying on table during repair, they might have got an air lock. Can you rev engine? Sounds bad but sometime with bad air lock, first start can be done only at full throttle immediately when she fires up. Did you put injectors back at original cylinders (ECU coding right)?

 

[Ml280amg]

Hi and thanks for your reply. We didn't take the injectors out during the repair. We only took the right hand side fuel rail off in order to get room to remove the manifolds. Left hand side was untouched. The engine idles a little lumpy and revs to around 3/3.5 thousand revs while in park. She does drive but lacks power during acceleration and the engine management light is illuminated.

 

[mersum1es]

So it is in limp mode... no other codes than rail overpressure? Codes comes back after reset? At what engine conditions when code triggers (rpm, pressure)? What reader you are using, I highly recommend SDS...

You might have got some dirt in fuel system, or you have bad connection somewhere (pressure sensor is at right rail).

 

[ajlsl600]

Note,clear codes.what comes back up ? Go from there.

 

[mattkh]

I would check the wiring to the rail pressure sensor and the harness. What color are the wires to the sensor?

 

[Ml280amg]

Thanks all. If I clear the code the engine light goes off until I start driving it again but then comes back on and throws the same code. I only have a cheap obd11 code reader thought, like a £30 job.I thought maybe wiring but when I unplug the sensor while running the car cuts out and then wont crank again until I plug it back in so thought the wiring/sensor must be ok??
Forgot to mention also when you try and accelerate hard there is no power but does throw out a lot of black smoke from the exhausts.

 

[mersum1es]

it should start in limp mode when sensor unplugged...

yep, black smoke means problem in boost pressure

 

[Ml280amg]

So would you focus on the wiring? Could it be a possible airlock? I can't get it to a garage until 4th jan to get it plugged in by somebody with a tidy code reader. Just thought I'd have a tinker myself in the time being. Would it be narrowed down to just a few possible causes or could it be anything more serious?

 

[Doug1234]

Check the fuel filter pipe connections to ensure they are the correct way around.
I remember a thread a while back where something similar occurred but cannot remember all the details.
I am probably wrong but do check them anyway.