Welcome, Guest. Please login or register.
Did you miss your activation email?
Sign in with Facebook Sign in with Twitter Sign in with Google Sign in with Linkedin Sign in with Microsoft

Hello! Welcome to the Ford and Volkswagen MPV / SUV Forums.
Dedicated forums for the Ford Galaxy, S-Max, C-Max, B-Max and Kuga.
User groups for the SEAT Alhambra, Volkswagen Sharan, Touran, Tiguan and Touareg!

Owners Forums for Ford and Volkswagen MPVs / SUVs

Ford Galaxy S-Max C-Max B-Max Tourneo Connect / Volkswagen Sharan Touran Tiguan Touareg Caravelle / SEAT Alhambra Alteca 

 Mk1 and Mk2 VW Sharan  Mk1 and Mk2 Ford Galaxy  Mk1 and Mk2 SEAT Alhambra  Ford C-Max B-Max  VW Tiguan  VW Touran  Mk3 Ford Galaxy  Mk3 VW Sharan  Mk3 SEAT Alhambra  VW T4 T5 Caravelle Transporter  Ford Tourneo Connect  VW Touareg

Advert:


Recent Forum Topics:

Google Translate:

Ford Galaxy / VW Sharan / SEAT Alhambra Forum:

Author Topic: Limp Mode - Boost pressure P0299  (Read 132 times)

Offline coursie77

  • *
  • Posts: 2
  • Thanked: 1
  • Model: Sharan Mk3
  • Spec: 1968cc TDI
  • First Name: Steve
  • Region: East Anglia
Limp Mode - Boost pressure P0299
« on: August 18, 2020, 11:10:36 AM »
Hi,

My first post but i am at a loss with my VW Sharan 2015 plate 2.0L TDI.

I have had a Boost pressure problem.  Under load it goes into limp mode.  The garage have read fault code P0299 and so far replaced actuator, replaced vacuum pump, changed boost pressure sensor.  It has been vacuum tested for leaks, exhaust system checked for air flow, EGR function tested.  On test the actual boost pressure only gets to 847mb and not the expected 850mb.  The air mass meter was also tried from a donor car but still no remedy to the fault.

My independent VW specialist has suggested taking to a dealership for further investigation - but that sounds expensive.

Anybody have any ideas?

Thanks in advance

Offline SirDavidAlhambra

  • Sir David Alhambra.
  • *
  • Posts: 550
  • Thanked: 10
  • Model: Alhambra Mk2 Auto
  • Spec: 2006 1.9 Tdi auto
  • First Name: Dave
  • Region: South East
  • Country: United Kingdom
Re: Limp Mode - Boost pressure P0299
« Reply #1 on: August 18, 2020, 11:53:25 AM »
Might be a duff turbo, carbon build up in the turbo vanes maybe meaning that it’s letting air out or something like that?

I had a garage like that once, they changed everything except the turbo itself. It was like they were philosophically opposed to the concept of a turbo ever being the source of a turbo related problem

“When all else fails, if u have tried everything else, then the only solution remaining now matter how improbable, must be the answer”

Others on here will be much more familiar with this conundrum I am sure

 welcome5 clapping and jumping
I drive a Seat Alhambra 1.9Tdi which has 115bhp and an automatic gearbox.

I am happy to help you with all your questions. I am not a qualified mechanic but seem to be better at fixing my car than even the most experienced garages.

I have lots of friends here and very much enjoy talking with you all.

Always remember, a motor car is a serious tool and should be treated with respect. Put your safety first, always.

Offline coursie77

  • *
  • Posts: 2
  • Thanked: 1
  • Model: Sharan Mk3
  • Spec: 1968cc TDI
  • First Name: Steve
  • Region: East Anglia
Re: Limp Mode - Boost pressure P0299
« Reply #2 on: August 18, 2020, 12:10:51 PM »
Thanks for the reply - I left the car with them while on holiday and expected the result to be a new Turbo (i am covered by a warranty on that front) but, yes, they do seem to be going down the route of it must be something other than the turbo itself!

Offline brianh

  • *
  • Posts: 799
  • Thanked: 74
  • Model: Galaxy Mk2
  • Spec: 2001 2.3 Ghia LPG
  • First Name: Brian
  • Region: South East
  • Country: United Kingdom
Re: Limp Mode - Boost pressure P0299
« Reply #3 on: August 18, 2020, 11:07:28 PM »
I'd be inclined to try getting them to compare that test result (the 847mb one) to a working vehicle of the same type, I would expect 850 is the minimum it should see, and if its not reaching that it only really leaves the turbo or a problem with the air intake system

(if that hasn't been apart already checking it isn't something daft like a carrier bag or similar stuck somewhere in the intake or air filter housing would be a good idea before trying the dealership, though would expect thats already been ruled out by the folks you've taken it to and should have been seen if they have looked at the functioning of the MAF anyway, but worth checking just to be sure before considering taking it to the dealer as it doesn't look like any of that side has been touched from what you've said, though they may have already done so).

It won't cost anything to ask the dealership how much it will be to have a look at it, though doubt it will be cheap if its not covered by warranty.


Offline johnnyroper

  • *
  • Posts: 2942
  • Thanked: 147
  • Model: Galaxy Mk2
  • Spec: 02 tdi 115 ghia
  • Region: South West
  • Country: United Kingdom
Re: Limp Mode - Boost pressure P0299
« Reply #4 on: August 18, 2020, 11:17:21 PM »
That pressure reading 847mb instead of 850mb is not an issue as it’s so small, when that reading was taken was it just revving I’m neutral? 2.0 cr tdi boost to approx 1.5 bar max under load. Have they done any logs to see what the actual out put is when driving? Ideally it needs to be a log as you can see the specified boost to actual boost curve

I assume basics like air and fuel filters have been checked?

Assuming no boost leaks,map,maf and vac system are good it only leaves sticking vanes or damaged turbo.

Boost issues aren’t really that complicated to figure out if you are methodical,I would question the VW specialists diagnostic skills if I was you.

Offline SirDavidAlhambra

  • Sir David Alhambra.
  • *
  • Posts: 550
  • Thanked: 10
  • Model: Alhambra Mk2 Auto
  • Spec: 2006 1.9 Tdi auto
  • First Name: Dave
  • Region: South East
  • Country: United Kingdom
Re: Limp Mode - Boost pressure P0299
« Reply #5 on: August 18, 2020, 11:27:11 PM »
Sounds to me like they’re barking up the wrong tree and missing the obvious. Maybe take a quick look at the air filter, however I would have thought the answer to this one woukd be easy for an experienced mechanic to work out.

Instead of clutching at straws and fiddling about with theoretical possibilities in a trial and error sort of way, it might be better for them to think about a more obvious conclusion... turbo.
« Last Edit: August 18, 2020, 11:36:28 PM by SirDavidAlhambra »
I drive a Seat Alhambra 1.9Tdi which has 115bhp and an automatic gearbox.

I am happy to help you with all your questions. I am not a qualified mechanic but seem to be better at fixing my car than even the most experienced garages.

I have lots of friends here and very much enjoy talking with you all.

Always remember, a motor car is a serious tool and should be treated with respect. Put your safety first, always.

Offline brianh

  • *
  • Posts: 799
  • Thanked: 74
  • Model: Galaxy Mk2
  • Spec: 2001 2.3 Ghia LPG
  • First Name: Brian
  • Region: South East
  • Country: United Kingdom
Re: Limp Mode - Boost pressure P0299
« Reply #6 on: August 18, 2020, 11:33:45 PM »
It wouldn't drive the turbo properly as the turbo is driven off the exhaust. Partially blocked exhaust would impede flow, the flow drives the turbo, hence it wouldn't drive it as it should.

Same applies on the air side as Johnnyroper says above, if it can't suck enough in due to the bits hes highlighted (though you'd hope they checked the air filter it would be wise to be sure!) you won't get the boost as theres not enough air there to compress in the first place.

Offline SirDavidAlhambra

  • Sir David Alhambra.
  • *
  • Posts: 550
  • Thanked: 10
  • Model: Alhambra Mk2 Auto
  • Spec: 2006 1.9 Tdi auto
  • First Name: Dave
  • Region: South East
  • Country: United Kingdom
Re: Limp Mode - Boost pressure P0299
« Reply #7 on: August 18, 2020, 11:40:04 PM »
Hehe sorry Brian, I edited my post while you must have been tapping out your response.

For everyone else’s benefit - I suggested originally that checking the exhaust flow was a crazy line of diagnosis but then I realised (as Brian rightly points out!) that the turbo is of course driven by the exhaust gases lol. So maybe not such a crazy thing to check after all  ;)
I drive a Seat Alhambra 1.9Tdi which has 115bhp and an automatic gearbox.

I am happy to help you with all your questions. I am not a qualified mechanic but seem to be better at fixing my car than even the most experienced garages.

I have lots of friends here and very much enjoy talking with you all.

Always remember, a motor car is a serious tool and should be treated with respect. Put your safety first, always.

 

Related Topics

  Subject / Started by Replies Latest
1 Replies
3568 Views
Latest October 24, 2012, 06:59:32 PM
by Mirez
10 Replies
6424 Views
Latest December 11, 2012, 12:51:03 AM
by robbieged
9 Replies
5911 Views
Latest February 07, 2015, 03:27:25 PM
by Chrispb
7 Replies
5793 Views
Latest January 09, 2017, 12:24:03 PM
by Chrispb
9 Replies
7460 Views
Latest December 23, 2015, 03:22:44 PM
by johnnyroper
25 Replies
1572 Views
Latest March 02, 2018, 07:01:06 PM
by johnnyroper

Advertisement: