Go Back   The Navara Forum > D40 > D40 Engine

Reply
 
Thread Tools Display Modes

Turbo Overboost
  #1  
Old 10-02-2018, 05:00 AM
Bosley99 Bosley99 is offline
Junior Member
 
Join Date: Jun 2015
Location: Sydney
Posts: 5
Default Turbo Overboost

Having problem with turbo overboost. Replaced turbo pressure sensor and solenoid and thought all was good when driving around ... normal max around 18psi.
This morning drove for around 40 mins all good. Reached Mt Ousley (long & steep) all OK in the first half of the climb then changed down to 4th and the boost pressure increased ... up to the 35 psi max on my auto meter gauge. I backed off as much as I could but the pressure was still well above 20 psi until I reached the top of the mountain.
Turned around and drove down the hill and stopped for over an hour just in case it was heat related (I'm running out of possibilities). No code thrown (I have a scan gauge).
Continued home (about 30kms) keeping boost as low as I could get. Took it out for a drive around the block after a few hours and same behaviour i.e. I can get boost to 35psi without too much effort on the flat.
No performance issues i.e. if I didn't have the gauge I wouldn't know there was a problem. The gauge moves normally i.e. nothing jerky, smooth as you would expect. It's like there's no pressure limit.
The only other out there possibility I can think of is that under load and heat the turbo vanes stick. Don't think it's the gauge because it behaved normally to the overboost trigger point.
Would appreciate any educated advice. I haven't been able to find any other situation like this having spent quite a lot of time researching.
Reply With Quote
Sponsored Links

  #2  
Old 10-02-2018, 06:52 AM
bods's Avatar
bods bods is offline
Advanced Member
 
Join Date: Sep 2010
Location: Orelia, WA
Posts: 4,621
Default

Could be sticky vanes. What does it drive like down low? It is really sluggish taking off from a stop or does it feel normal?
Reply With Quote

  #3  
Old 10-02-2018, 07:25 AM
Bosley99 Bosley99 is offline
Junior Member
 
Join Date: Jun 2015
Location: Sydney
Posts: 5
Default

Not sluggish. Drives really well, just like before I had the problem.
Disconnected the vacuum tube from the actuator to see if the vanes were stuck in the open position. No boost at all so I guess the actuator is doing what it is supposed to do. By the way it’s a 2007 stx.
Reply With Quote

  #4  
Old 10-02-2018, 08:53 AM
bods's Avatar
bods bods is offline
Advanced Member
 
Join Date: Sep 2010
Location: Orelia, WA
Posts: 4,621
Default

I take it the gauge reads zero when the motor is turned off? Is it a mechanical or electronic gauge?
Reply With Quote

  #5  
Old 10-02-2018, 09:13 AM
Bosley99 Bosley99 is offline
Junior Member
 
Join Date: Jun 2015
Location: Sydney
Posts: 5
Default

Yes at zero with the engine turned off. Does the full range i.e. 0 through to 35 whilst driving.
It’s mechanical.
Reply With Quote

  #6  
Old 10-02-2018, 09:20 AM
ericcs's Avatar
ericcs ericcs is offline
Senior Member
 
Join Date: Jan 2011
Location: birkdale brisbane
Posts: 476
Garage
Default

maybe get an obdii bluetooth plug and use an android phone with the torque app. to compare boost readings.
would think if your boost is near doubling, the car would have some different performance characteristics!
Reply With Quote

  #7  
Old 10-02-2018, 09:36 AM
bods's Avatar
bods bods is offline
Advanced Member
 
Join Date: Sep 2010
Location: Orelia, WA
Posts: 4,621
Default

^^that would be my next move. Autometer are good quality, I have them in mine and have never had a problem. That isn't to say something internal hasn't failed in the gauge and giving an incorrect reading.
Reply With Quote

  #8  
Old 10-02-2018, 11:15 AM
Old.Tony's Avatar
Old.Tony Old.Tony is offline
Administrator
 
Join Date: Oct 2009
Location: Mid Coast Region, NSW, Australia
Posts: 14,869
My Mood:
Garage
Default

Scangauge ought to show boost pressure too, shouldn't it? If not, the OBD adapter + Torque app is the way to go.

Turbocharger overpressure will do several things:

1) Make your vehicle performance change. Usually feels a little more powerful, and no sign of black smoke

2) Throw a "turbocharger overpressure" engine code. Mine's done it when the hose popped off my Tillix valve and the turbo was given full "go". Engine light came on with that exact error.

3) Pop the hose off the intake manifold. This happened to me moments after the hose popped off the Tillix valve. I saw my boost pressure skyrocket then heard a 'pop' from under the bonnet, checked the mirror and sure enough the caravan had disappeared in a cloud of black smoke. Quickly pulled over (don't want to run unfiltered air for too long) and put it all back together.

So, I would suspect a faulty gauge too, like the others.
__________________

Check out the FAQs by clicking here!



"Money can't buy happiness, but it does make misery a lot easier to deal with."
Reply With Quote

  #9  
Old 10-02-2018, 02:46 PM
Czechmate's Avatar
Czechmate Czechmate is offline
Member
 
Join Date: Apr 2016
Location: South Australia
Posts: 257
Default

Errm i got a 2007 stx too theres no variable vane turbo on that rig mate
Shes an old school garrett setup
variable vane electronic turbo started in 09 i think?
Correct me if im wrong

Also if you're boosting at 35 psi you'd friggin know about it
Thats a lotta boost
Gotta be a faulty gauge surely...
Reply With Quote

  #10  
Old 10-02-2018, 10:52 PM
ericcs's Avatar
ericcs ericcs is offline
Senior Member
 
Join Date: Jan 2011
Location: birkdale brisbane
Posts: 476
Garage
Default

Quote:
Originally Posted by Czechmate View Post
Errm i got a 2007 stx too theres no variable vane turbo on that rig mate
Shes an old school garrett setup
variable vane electronic turbo started in 09 i think?
Correct me if im wrong

Also if you're boosting at 35 psi you'd friggin know about it
Thats a lotta boost
Gotta be a faulty gauge surely...
i was under the impression all d40's had variable vane turbo's, pre 09's are vacuum, post are electronic. D22's are fixed vane.i had vacuum leaks, resulting in the actuator not closing the vanes, so they were open all the time. this slowed the boosting and made the car much louder
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT +1. The time now is 04:59 PM.



Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
| Home | Register | FAQ | Members List | Calendar | Today's Posts | Search | New Posts |