Hi there , good evening to you

Ok the first thing that MUST be done with this issue is to have a diagnostic fault code check done
This is imperative to correctly diagnosing this issue first time
These engine management systems are very technical and complex do without a fault code you can cost yourself a lot of time and money as you are really just guessing which sub system the fault lies with without a code

Common faults on this vehicle are camshaft sensor faults
MAP sensor faults (boost sensor ) corroded wiring to the fuel pump
Worn injectors causing excess fuel to leak back causing limp home mode (glow plug light flashing )
Cylinder head temp sensor faults and various other issues
This is why a fault code check is so important with this type of issue

if you need anymore help or advice on this issue please let me know
if you are completley satisfied with my answer/advice PLEASE CLICK ACCEPT
Kind regards XXXXX XXXXX and have a nice evening

Brian