2001 gu2 zd30 boost nightmare

Hi All.

I've been at it for a few days now. But it's been an issue for a while now. I've been having a long battle with boost. Read as much as I can but I'm hitting a wall

As mention 2001 GU2 Patrol ZD30 having boost issue.

Dawes & Needle Valve, EGR Block, Catch can, Cross Country Intercooler all installed. 6+ years now

I replaced boost and EGT gauges for better readings. Previous owner installed EGT and a boost gauge that had negative values both was cheapies from the bay. Replaced with SAAS muscle digital series.

Most recent issue is very low boost. 5psi if i give it alot.


- Checked and cleaned Dawes. Added more pressure on the ball no change.
- Turned the needle all the way down (closed) also backed it off in 1/2 turn intervals no noticeable difference
- Cleaned the MAF sensor.
- Pulled the intercooler off, cant see any oil spray, stains signs of leak on intercooler.
- Checked all the hose and clamps from throttle to intercooler to turbo - no stains or signs of leak, no damage or hole I can see.
- I've replaced all 4mm hoses that I know of.

And this is about where my understanding taps out.

- I know the waste gate actuator goes down when I pull the line off it and up when I push it on.
- I also have vacuum from the vacuum pump, not sure how strong should it be?

I need some help on what to check next, as well as how to check the actuator and vacuum pump are working correctly.

Cheers
Richard

Quote:

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Originally Posted by DickieO

Hi All.

- I know the waste gate actuator goes down when I pull the line off it and up when I push it on.
- I also have vacuum from the vacuum pump, not sure how strong should it be?

I need some help on what to check next, as well as how to check the actuator and vacuum pump are working correctly.

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Richard, the VNT actuator (you refer to it as: the waste gate actuator), appears to be working correctly.

There appears to be adequate vacuum at the VNT actuator as the rod moves up with vac hose connected and then drops down when hose is pulled off "with engine at idle".

CHECK _ With eng at idle (hose connected /rod up): is the actuator rod / lever resting against the vane limit stop screw.

FYI, Full vacuum at actuator with engine at idle is nom 23"Hg (inches of mercury _ vacuum)

Be worthwhile to use a scan tool and check for any fault codes. Clear them but but first record any if reported?

Are you running a stock ECU?

What was the max boost, if you know the level before current boost issue?

Maybe a limp fault causing problem.
We can test VNT turbo boost response with bypassing manual boost control _ need to check and action above first.

Quote:

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Originally Posted by Bidja

Richard, the VNT actuator (you refer to it as: the waste gate actuator), appears to be working correctly.

There appears to be adequate vacuum at the VNT actuator as the rod moves up with vac hose connected and then drops down when hose is pulled off "with engine at idle".

CHECK _ With eng at idle (hose connected /rod up): is the actuator rod / lever resting against the vane limit stop screw.

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The actuator rod does not reach the vane limit stop screw when idling. *After a bit of google to figure out that its not the two bolts on the actuator arm hahah*

Quote:

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Originally Posted by Bidja

FYI, Full vacuum at actuator with engine at idle is nom 23"Hg (inches of mercury _ vacuum)

Be worthwhile to use a scan tool and check for any fault codes. Clear them but but first record any if reported?

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I don't have a Auto Diagnostic Scanner, I'll see if i can borrow one locally or I'll pick one up for myself.

Quote:

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Originally Posted by Bidja

Are you running a stock ECU?

What was the max boost, if you know the level before current boost issue?

Maybe a limp fault causing problem.
We can test VNT turbo boost response with bypassing manual boost control _ need to check and action above first.

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Correct running stock ECU.

Boost was running at 15psi.

Appreciate the help, eager to get back into it to figure this out.

Quote:

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Originally Posted by DickieO

The actuator rod does not reach the vane limit stop screw when idling. *After a bit of google to figure out that its not the two bolts on the actuator arm hahah*

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Good that u sorted out which was the correct screw for lever to rest against lol.


Now to confirm:

With manual boost control (Dawes and needle valve) connected, close needle completely (wind in clockwise):

At idle, is the lever now touching stop screw y/n?

If it does not, connect the vacuum hose from vac supply point (on DI, think it is just under front of intercooler), connect this hose direct to the actuator diaphragm (refer pic: finger on red hose is the place). Lever should now rest hard against the stop screw with engine at idle y/n?

Have these issues happened straight after replacing the gauges? Or was it fine, then some time later the boost issue arose?

Thanks Bidja.

TESTED - Needle valve completely closed, at idle the lever does not touch the stop screw.

TESTED - I connected the Vac supply directly to the VNT diaphragm and the lever does not touch the stop screw. Appears to be the same amount as when to T piece.

I have attached images showing hose locations in case I got this wrong somehow. I also added the Needle/dawes diagram that my system is set up as.

Mudski - no unfortunately this occurred before attaching new boost gauge. Original gauge was not a diesel boost gauge style and needed replacing.


Attachment 86991Attachment 86992Attachment 86993

Quote:

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Originally Posted by DickieO

Thanks Bidja.

TESTED - Needle valve completely closed, at idle the lever does not touch the stop screw.

TESTED - I connected the Vac supply directly to the VNT diaphragm and the lever does not touch the stop screw. Appears to be the same amount as when to T piece.

I have attached images showing hose locations in case I got this wrong somehow. I also added the Needle/dawes diagram that my system is set up as.

Mudski - no unfortunately this occurred before attaching new boost gauge. Original gauge was not a diesel boost gauge style and needed replacing.

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VNT actuator lever needs to touch stop screw.

Can buy a vac gauge from Repco to check vac level in line. I have one connected all time to observe vac on the VNT actuator on the fly (driving)_provides indication of vane closure position.

Also need to check that the VNT vanes have not been clogged up with carbon/soot preventing vanes from closing. Post a pick of the actuator rod showing the thumb wheel adjuster paint marks on it for locked setting position and check that the thumb wheel cannot rotate(eg: lock nut needs to be done up _ refer to my pic posted above of actuator/diaphragm).

Can suck like "crazy" on hose connected to actuator diagram and see if rod will rise (lever to rest against stop). I have a hand operated vac pump for this as my lungs would not like sucking on the hose so hard..haha

https://www.repco.com.au/tools-equip...184/p/A9445092

Gauge is not expensive.

If vacuum for both hook ups (needle closed and direct vac hose connection), is above say 13-18"Hg and lever still does not touch stop screw we need to disconnect actuator rod from lever pin to see if the lever can rise/fall freely and should give a slight clang noise as vanes open / close to their limits. Could also indicate someone has changed the actuator thumb wheel setting (all in good time). FYI _ Can also undo the two nuts holding the actuator diaphragm in place to help remove lever from rod pin/pivot. Need to tie a piece of fishing line to the e-clip at pivot and secure the line to A/C hose or similar so not to loose clip when removed (trust me it will fly).


Do one thing at a time and record result.

I saw something from the suppliers of Dawes and tilling valves the other day about these systems starting to play up.
And simply. The age of the hose its deterioration.
So it's suggest before to fiddle too much just replace all the vacuum hoses.
Probably $20 worth.
Imo they are very simple, set and forget setups.
So if your seeing a failure I doubt it would be the valves, especially if your using filtered air on your needle valve.

Sent from my SM-S916B using Tapatalk

Thanks again Bidja, my lungs arent ready for a whole lotta crazy sucking haha

I got my list for a morning run to Repco, 3mm Vac Hose and Vac Guage. Sweet!

I also purchase an ECUTalk Cable to check if there is a code.

3 hours of research cause of that damn fake OBD2 plug. Looked is at Nisbie bluetooth aswell, real confusing.


Thanks BigRAWesty - I did replace all the vac hose but with 4mm, I read it shoud be 3m so i'll replace it all again.

As Kallen says, do agree most of the times it is vacuum failure that cause the poor operation of Tillix or Dawes manual boost control setups.

Reason for getting the vac gauge from Repco, to check vacuum level in system. Be interesting, before u start changing out hoses, check the full vac at supply take off and then T the gauge into the vac hose just before actuator(measure level at idle). As mentioned full vac is around 23"Hg at supply point and at the actuator with rod fully up is around 12-14"Hg.

BTW, DI has a consult comms port not OBD2.

Apologies for the delay. Work commitments.

Purchased a Vac tester and the ECU Talk cable was delivered.

Vacuum Testing Results: with Needle valve completely closed

T added Piece before VNT actuator = 12"Hg

VNT actuator receiving = 28"Hg

ECU Results:

Quote:

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BTW, DI has a consult comms port not OBD2.

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This is the plug i have on the patrol. (PIC)

The ECU Talk cable I got was able to give me the following codes using my laptop.

Code 73: P3-Pump Comm Line
Code 95: Turbo Pressure

Cleared the codes but no change.



Is my next step disconnecting the VNT actuator rod to see if rod moves freely? I have attached a pic of the VNT actuator at idle, still not touching the stop screw

Do i need to check vanes now to see if theyre clogged?

Thanks


Attachment 87041Attachment 87042

Quote:

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Vacuum Testing Results: with Needle valve completely closed

T added Piece before VNT actuator = 12"Hg

VNT actuator receiving = 28"Hg

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So at idle, are u saying that with either the vac supply measuring 12 "Hg when T'd into vac line with Dawes connected and also when vac supply of 28 "Hg connected directly, that in both cases the lever is not touching the stop?

Have you seen the rod move at all?

If pic shows the typical rod position with both vac conditions at idle, I would check if u can move the lever up and down with actuator rod disconnected. After removal of the e-clip at lever pivot u will probable need to undo the two securing nuts that hold the actuator to the brkt so u can tilt the actuator to the side for rod to slip off lever pivot pin. Note: Tie fishing line to the clip and anchor it so u do not loose clip when u remove it.

Maybe the diaphragm in the actuator has failed (split)_can u check and see if the actuator can hold a vac after the eng is turned off?

Quote:

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Originally Posted by Bidja

So at idle, are u saying that with either the vac supply measuring 12 "Hg when T'd into vac line with Dawes connected and also when vac supply of 28 "Hg connected directly, that in both cases the lever is not touching the stop?

Have you seen the rod move at all?

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Correct, motor is idling the rod doesnt touch the stop, yes i have seen the rod move, i can remove the line and the rod will fall reconnect and move up but not all the way to reach the stop screw.

Quote:

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Originally Posted by Bidja

Maybe the diaphragm in the actuator has failed (split)_can u check and see if the actuator can hold a vac after the eng is turned off?

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sorry might sound stupid but i couldnt find how to test the actuator holds vacumm without using a vacuum hand pump. could you explain this for me? or does one person watch the actuator while all lines are attached normally and another shut of the engine and see if it hold position?

I'll give it a go in the morning and get the arm off and check it out aswell. Thank again

https://youtube.com/shorts/KrSph68NJ_0?feature=share

If you have access to a vac hand pump to test if actuator holds vacuum this would be good. I have one and use it to set up my actuator rod length.

Could fit a needle valve between supply vac hose (supply 28"Hg) and actuator, apply vacuum then close needle (if it seats well) and turn eng off see if rod holds/drops away.

BTW the video shows that the rod lifts only about 5mm, normal travel is about 10mm. Would remove the actuator rod from lever and check the lever / vane movement manually.

Quote:

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Originally Posted by DickieO

Attachment 87042

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See that the witness mark on the actuator rod assy is very faint get a marker and redo it so we have a baseline set point.

There appear not to be a corresponding mark on the hex adjuster nut ?

Actuator doesnt seem to hold vacuum.

Had the engine running with needle open connected before the actuator (rod was up). With the engine still running as I would closed the valve the actuator would drop.

Is this the witness mark you mentioned? nuts seem tight, i haven't adjusted them so they don't look like they've moved.

If i need to replace the actuator, should i look into getting a hand vac aswell?

Attachment 87044

Looks much like the actuator needs replacing.

This the pump I bought:
https://mityvac.com.au/product/mityv...hand-pump-kit/

Can get cheaper without all the fittings which you do not really need
https://www.ebay.com.au/itm/19287347...BoCdcYQAvD_BwE


With the rod/adjuster marking, have a look at my pic at post No 4 and the adjuster thumb wheel is the knurled wheel in your case it is a hex profile nut adjuster _ mark across the adjuster nut and the rod arm (reference set point).

https://www.dieselsmart.shop/


https://www.berrimadiesel.com/products-services



These guys replace the VNT vac actuators with a positive pressure actuators (do away with vacuum control).

Coudl give them a call and they may help with supply of vac actuator. Get later model like off a CRD.

Compare costs. Beware of second hand ones (at least these blokes would test it I would recon)..

Ordered a new actuator. Decided to go with the vacuum on for ease of replacing as time is of the essence, should be here in a couple of days.

I did give the mob a call about the boost actuators. They recommended a tune when installing them because getting the right amount of boost can be tricky, could be done yourself with trial and error but i will save that for another time.

@dickie0 Not clear what u intend to do here?

As the lever does not touch the stop screw when u connected the vac supply to direct to the actuator (measured at 28"Hg) and actuator does not hold vacuum, yes you most likely need a new vac actuator.

Need a hand operated vac pump to set actuator rod length (makes is a lot easier). Also can be used to check the diaphragm in the actuator for leaks.

Need to remove you current actuator and check that actuator lever can move freely all the way up to the stop screw. Check for vane operation.

Quote:

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Originally Posted by DickieO

Ordered a new actuator. Decided to go with the vacuum on for ease of replacing as time is of the essence, should be here in a couple of days.

I did give the mob a call about the boost actuators. They recommended a tune when installing them because getting the right amount of boost can be tricky, could be done yourself with trial and error but i will save that for another time.

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Not clear what u intend to do here?

As the lever does not touch the stop screw when u connected the vac supply direct to the actuator (measured at 28"Hg) and actuator does not hold vacuum, yes you most likely need a new vac actuator.

Need a hand operated vac pump to set actuator rod length (makes is a lot easier). Also can be used to check the diaphragm in the actuator for leaks.

Need to remove you current actuator and check that actuator lever can move freely all the way up to the stop screw. Check for vane operation.

Quote:

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Originally Posted by Bidja

Not clear what u intend to do here?

As the lever does not touch the stop screw when u connected the vac supply direct to the actuator (measured at 28"Hg) and actuator does not hold vacuum, yes you most likely need a new vac actuator.

Need a hand operated vac pump to set actuator rod length (makes is a lot easier). Also can be used to check the diaphragm in the actuator for leaks.

Need to remove you current actuator and check that actuator lever can move freely all the way up to the stop screw. Check for vane operation.

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Im going to try get a hold of a Hand vac pump from a mate to borrow. if not i'll purchase one.

I had removed the rod and checked and the vane moves freely before purchasing the actuator, should of mentioned that.

The fishing line trick worked a treat for me on the c clip. Spinning the clip around to the back has an easy slot to thread the line in.

https://youtube.com/shorts/4j6kbu1NCdE?feature=share

Do you know the Hg values I should be aiming for once installed using the vac pump on the actuator? if not i'll try find them.

Quote:

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Originally Posted by DickieO

Im going to try get a hold of a Hand vac pump from a mate to borrow. if not i'll purchase one.

I had removed the rod and checked and the vane moves freely before purchasing the actuator, should of mentioned that.

The fishing line trick worked a treat for me on the c clip. Spinning the clip around to the back has an easy slot to thread the line in.

https://youtube.com/shorts/4j6kbu1NCdE?feature=share

Do you know the Hg values I should be aiming for once installed using the vac pump on the actuator? if not i'll try find them.

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The video is good mate. One comment here is that the lever should move up/down with ease there appears to be a small amount of resistance in the top part of travel (say top 5mm), it should just float up/down with finger and it will give a metallic clang type sound at the ends of travel.

May be a little soot / carbon clogging up the vanes. Lets see how it goes with the new actuator but I would like to see it move more freely.

Could slip the actuator rod back onto pin and with the hand vac pump apply say 15"Hg and see how it lifts.

With the new actuator, initially adjust the rod length to a point where the lever just touches the stop screw with 13-14"Hg.
As you operate the hand vac pump, the rod starts to lift, you will notice the vac level increase progressively on the pump gauge.

After you set the rod length (13-14@Hg), connect the vac supply direct (28"Hg) and check at idle that the rod lifts and lever rests against stop then the pull hose of actuator and the rod should drop.

If all good connect up the manual boost control, start eng (close the needle valve) and the lever should be resting against stop and then open needle to where the rod just starts to drop.
All good, then take it for a gentle drive set the Dawes to max boost of 15psi, then recheck that lever is just touching stop.

Let us know how she goes. Observe if it is laggy or aggressive(jerky) at low revs at early spool. Learn as we go.

Not many tuners out there set up actuators.

Tested the old actuator and couldn't hold any vacuum with the pump. Tested the new one and did perfectly.

Followed the steps, lever is now hitting the stop screw when running!! And we now have good boost!!

Took a little bit to set the dawes to 15psi after mucking around with it a lot before starting this thread, took it for a very easy drive and honestly if felt really nice. Drove around for about 20 minutes no spikes, no high EGT, didn't feel laggy, responsive but not jerky.

Very happy at the moment, anything else i should be checking now things seem to be working properly/better?

Quote:

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Originally Posted by DickieO

Tested the old actuator and couldn't hold any vacuum with the pump. Tested the new one and did perfectly.

Followed the steps, lever is now hitting the stop screw when running!! And we now have good boost!!

Took a little bit to set the dawes to 15psi after mucking around with it a lot before starting this thread, took it for a very easy drive and honestly if felt really nice. Drove around for about 20 minutes no spikes, no high EGT, didn't feel laggy, responsive but not jerky.

Very happy at the moment, anything else i should be checking now things seem to be working properly/better?

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Great result_pleased for you.

Drive it for a while see how she goes, may be able to increase boost to 16 psi.

List all eng mods you have/know of and we can go from there.

i went and bought the same actuator, installed it yesterday ($50 ebay), rod starts to lift at 5"Hg as it should and then applied 20"Hg (held vacuum) _ yes good product working well.

Quote:

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Originally Posted by Bidja

List all eng mods you have/know of and we can go from there.

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Not much out of the ordinary.

Engine rebuild at 215k

Nads (Dawes, needle, catch canister, boost and egt guage, EGR blank plate)
Cross Country 4x4 Intercooler
From what I'm aware a glowplug timer was also installed. I dont know much about them so Ive just left it as is.

Glad to hear you had a good experience with the actuator install as well.

Quote:

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Originally Posted by DickieO

Not much out of the ordinary.

Engine rebuild at 215k

Nads (Dawes, needle, catch canister, boost and egt guage, EGR blank plate)
Cross Country 4x4 Intercooler
From what I'm aware a glowplug timer was also installed. I dont know much about them so Ive just left it as is.

Glad to hear you had a good experience with the actuator install as well.

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Read your first post again and also noted the eng mods.

Really what you have currently is adequate.

They like to breathe well (induction), maybe a look at your air intake (airbox design and inlet piping to turbo). But this is dollars, so I would suggest to leave as is and drive for a while and enjoy.

Can try installing an extra needle valve and install this needle valve downstream of the Dawes boost controller. You set Dawes to a lower boost level eg: nom 8psi and then close this needle valve (the one downstream of Dawes), to obtain the target max boost (15-16psi). This setup will allow the VNT vanes to start to open earlier from say 8psi then gradually continue to open until you reach the target max boost.
The spool needle valve is adjusted just as you do currently (ie: lever resting against stop).

BTW what cruise boost are you getting @ 100kph / flat road?