Unhelpful error codes

[toppotter]

Vito 113 CDI W639, diesel, 134k miles, 2014

Recent engine warning light while on Motorway, loss of power, max speed about 65mph. Also loss of acceleration at low speeds.
My independent garage said the error code was confusing as it was a problem with the injectors but there was no problem with them. They did find a fault in the fuses and test drove it twice and the engine light stayed off.
I picked it up and felt the power was back for about 5 mins, then the engine light came back on and power reduced again. Back to the garage on Monday.
Any thoughts anyone?

 

[onefortheroad]

Egr , exhaust back pressure sensor amongst any number of possibilities.

 

[toppotter]

Sorry what's EGR?

 

[onefortheroad]

Exhaust gas recirculation

 

[LostKiwi]

I've generally found the description to the fault code quite helpful but it does depend on which code reader is used.
Codes are either generic or manufacturer specific but there's some overlap.
A generic reader may say one thing but a manufacturer specific reader will say something different.

It's quite possible your garage was using a generic reader and getting the wrong description.

What were the codes (numbers not descriptions).

 

[toppotter]

Exhaust gas recirculation

Thanks

 

[toppotter]

I've generally found the description to the fault code quite helpful but it does depend on which code reader is used.
Codes are either generic or manufacturer specific but there's some overlap.
A generic reader may say one thing but a manufacturer specific reader will say something different.

It's quite possible your garage was using a generic reader and getting the wrong description.

What were the codes (numbers not descriptions).

P027246

 

[ajlsl600]

EML - P027246 “Teach-in of the operating parameters for cylinder 4 has a malfunction. There is an error in the calibration or parameterisation memory | Engine

Hi all. I am looking for some help with my w212 E220 2014 with the OM651 engine. My engine management light appeared and after diagnosed with Star it came back with the following: P027246 “Teach-in of the operating parameters for cylinder 4 has a malfunction. There is an error in the...

forums.mbclub.co.uk

 

[alexanderfoti]

I've generally found the description to the fault code quite helpful but it does depend on which code reader is used.
Codes are either generic or manufacturer specific but there's some overlap.
A generic reader may say one thing but a manufacturer specific reader will say something different.

It's quite possible your garage was using a generic reader and getting the wrong description.

What were the codes (numbers not descriptions).

I know we all say this, but it really is true.

W204 in the workshop yesterday, customers snap on diag system said
"NSF ADS damping valve open circuit"

Xentry said "NSF body acceleration sensor open circuit"

 

[supernoodle]

P0272= Cylinder 4 Contribution/Balance
Failure byte of 46 means Calibration/parameter memory failure

The injector may be working, code suggests the adaption value is implausible.

 

[supernoodle]

As LK said, codes most certainly are helpful, but you have to understand what they are telling you. The mention of a component does not mean that component is faulty. In fact there are no codes that directly indict a component.
A fault code is just one tool that can help guide in diagnosing and resolving an issue.
Unfortunately there is a misconception that a reader turns any noob into a master mechanic.

 

[mioba]

As LK said, codes most certainly are helpful, but you have to understand what they are telling you. The mention of a component does not mean that component is faulty. In fact there are no codes that directly indict a component.
A fault code is just one tool that can help guide in diagnosing and resolving an issue.
Unfortunately there is a misconception that a reader turns any noob into a master mechanic.

Very true, especially for engine codes, they are pointers, but planting the flag needs further investigation.