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Discussion Starter · #1 ·
Hi Guys ,hoping someone can help.Just bought an ultra low miler 52 plate 3door thats bogging and going into limp mode.
The car instantly re sets when ignition is switched off and back on.
I'm based near durham and just had car to a specialist in meadowfield for belt,pump and service.He says the code is boost related but has only ever swapped out the complete turbo assembly and not done the actuator only.
Ive done the n75 and maf so think it is the actuator but need a guru who understands these issues and can sort for me.
Hoping one of you guys knows or can recomend someone to help would be greatly appreciated.
Ps car goes great when not in limp mode so pretty certain the turbos fine (only done 10k miles from new)
 

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Before buying anything, look up VNT cleaning.... most of the times the VNT mechanism is stuck. if that is the case you got only 3 options:
  • clean it
  • replace the turbo's CHRA (bought from a reputable place that actually balances the thing right)
  • buy a replacement (new or used) turbo.
 

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Discussion Starter · #4 ·
Before buying anything, look up VNT cleaning.... most of the times the VNT mechanism is stuck. if that is the case you got only 3 options:
  • clean it
  • replace the turbo's CHRA (bought from a reputable place that actually balances the thing right)
  • buy a replacement (new or used) turbo.
Thanks for the reply.Car runs great if gentle as if nothings sticking ,its if i rev it quickly up to its max that it bogs???Is there any chance it could be a failed turbo actuator?? Im not mechanically minded unfortunately so if i have to pay a garage should i bite the bullet and replace the turbo and actuator in one fell swoop!
 

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When the car runs idle with no load it will rev all the way even if the vnt is sticking or if it has a bad actuator... you could opt for a terraclean or replace the complete turbo after the actuator replacement doesn't sort it out.
 

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Discussion Starter · #6 ·
When the car runs idle with no load it will rev all the way even if the vnt is sticking or if it has a bad actuator... you could opt for a terraclean or replace the complete turbo after the actuator replacement doesn't sort it out.
The car will accelerate quickly to about 3k then above 3200 fluff and go into limp.If i switch ignition off and back on it will be fine and rev up to 4k consistently right through the gears.It seems to happen on first drive off but if i dont rev over 3kand be gentle i can drive all day with no issues.Sorry to sound thick but if the CHRA is the issue .should it drive 10/10 under 3k revs ??
 

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It'll slowly get worse if it's the VNT. When the turbo gets warm enough it might soften things up to get to the higher 4k before it starts acting up...
 
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