Vauxhall Insignia 2012 - Limp mode at motorway speed

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Hi all,
Looking for some informed opinions before I decide whether to keep throwing money at this or cut my losses. Currently at £500 spent

Problem:
  • Car is going into limp mode, only on motorway type journeys, when I hit 2500-3000rpm and 55-60mph. Problem started 6 months ago
  • Power drops suddenly, service light comes on
  • No issues when pottering around town
  • Turning ignition off and back on clears limp mode, but it returns again under load
  • After a few weeks, constantly in limp mode, cant get over 3000rmp, feels like no power
  • Has been in and out of garage all week
    • DPF pressure sensor changed, dpf cleaned out, regen forced. Test drove, went into limp mode
    • Changed boost pressure sensor (it was dirty looking inside), test drove, went into limp mode
    • Changed cylinder Pressure glow plug 2, test drove, went into limp mode
  • I gave garage list of extra items to check, but they cant find any issues
    • intercooler boost pipes for cracks
    • Exhaust gas sensor operational
  • They said they do not know what the problem is, so I am here looking for some support and suggestions.
Fault codes seen at various stages, when components changed:
  • P03A3 – Cylinder pressure sensor (cylinder 2) implausible
  • P2453 / P2458 – DPF differential pressure related
Car details:
  • 2012 Vauxhall Insignia
  • 2.0 CDTi diesel
  • 115k miles
  • Manual
  • DPF equipped

Appreciate any advice, thank you

Chris
 
Hi all,
Looking for some informed opinions before I decide whether to keep throwing money at this or cut my losses. Currently at £500 spent

Problem:
  • Car is going into limp mode, only on motorway type journeys, when I hit 2500-3000rpm and 55-60mph. Problem started 6 months ago
  • Power drops suddenly, service light comes on
  • No issues when pottering around town
  • Turning ignition off and back on clears limp mode, but it returns again under load
  • After a few weeks, constantly in limp mode, cant get over 3000rmp, feels like no power
  • Has been in and out of garage all week
    • DPF pressure sensor changed, dpf cleaned out, regen forced. Test drove, went into limp mode
    • Changed boost pressure sensor (it was dirty looking inside), test drove, went into limp mode
    • Changed cylinder Pressure glow plug 2, test drove, went into limp mode
  • I gave garage list of extra items to check, but they cant find any issues
    • intercooler boost pipes for cracks
    • Exhaust gas sensor operational
  • They said they do not know what the problem is, so I am here looking for some support and suggestions.
Fault codes seen at various stages, when components changed:
  • P03A3 – Cylinder pressure sensor (cylinder 2) implausible
  • P2453 / P2458 – DPF differential pressure related
Car details:
  • 2012 Vauxhall Insignia
  • 2.0 CDTi diesel
  • 115k miles
  • Manual
  • DPF equipped

Appreciate any advice, thank you

Chris

Check the turbo hose isn't split, or the intercooler system leaking.
 
Check the turbo hose isn't split, or the intercooler system leaking.
They said they checked it today, but I doubt they took it completely out and had a proper look. Its definitely something boost pressure related as it only happens on motorway, never limp mode local driving
 
They said they checked it today, but I doubt they took it completely out and had a proper look. Its definitely something boost pressure related as it only happens on motorway, never limp mode local driving

If your under bonnet area, is reasonably clean, look around the pipes and intercooler, for signs oil leakage.
 
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