GU ZD30 DI NADS Help

Hey guys, Long time lurker don't post much.

I have a GU ZD30 and auto. I have replaced the injector pump, injectors, and head within the last 10-15k kms.
I Blocked the EGR and fitted a boost gauge and drove around for a while. when cruising I would notice the boost gauge to spike to 20+ then fall away to around 10-15 and stay there while accelerating. while cruising on the freeway I could hear the intake change noise and the boost climb to 15 and sit there. But here's the issue.....

I have now fitted a Dawes valve to the car. 'No matter what I do whether it be full throttle or revving it out I can't get it to boost above 9-10psi. it barely gets to 5psi before 2500rpm and is just a slow bucket of puss :furious::furious::sterb003::sterb003:. I cant keep the EGT under 480 while cruising at 100 and I cant get it to accelerate without reaching EGTs of 500-550+. Why has the Dawes valve made the car worse n not better ??

Can anyone please help me?

you need to get your boost up to 10 psi for 100kph, your max will be around 15-18 psi with spikes to 20 maybe.
After you have your boost set right adjust the needle valve for your spool up rate
Take note where the dawes is now and screw it "IN" one full turn and lock it off.
Go for a drive and see what boost levels you are acheiving, keep doing this till max boost is as above

Cheers. I have gone from all the way out to all the way in on the dawes valve and still cant get anything above 9-10psi.... cruising at 100 im getting 4-5psi. when I give it a boot full its slowly climbs to 8psi but my EGTs rise stupidly like the ecu is expecting 15psi

Sometimes but certainly not always you need to slightly stretch the spring on the Dawes to get enough spring pressure to get the boost up.

Have you installed a needle valve aswell?

no needle valve yet. will be doing that Monday..
from what I read the needle valve improves the delivery and can select the range of the boost but not the maximum... When I installed the dawes valve I expected to lose the spikes of boost that go to 20 but not also reduce the peak to 10.

Was doing my head in adjusting the dawes and needle valve when I first installed it, ended up being MAF issues and once I sorted a replacement it was a lot better. Trying to get the same psi ranges with the auto at the speed and rev ranges suggested for installing the dawes valve was very difficult because of the Auto trans and how at 100 it sits in the low 2000 rpm range (2100-2200 there abouts instead of what the manuals sit at 2600-2700 maybe?), hope you figure it out soon, maybe double check its all plumbed correctly with no leaks.

On a flat road with cruise on my boost will sit at 4-6psi at 100k's with the auto, but rises quite easily with an incline or a bit of load.

Quote:

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Originally Posted by lil regy

no needle valve yet. will be doing that Monday..
from what I read the needle valve improves the delivery and can select the range of the boost but not the maximum... When I installed the dawes valve I expected to lose the spikes of boost that go to 20 but not also reduce the peak to 10.

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Worry about it once you have the needle valve in. Whilst the needle valve controls spool up and mid range boost it still affects max boost to a point.

cheers guys. will buy and install the needle valve Monday and et you know the result

Quote:

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Originally Posted by SG1

Was doing my head in adjusting the dawes and needle valve when I first installed it, ended up being MAF issues and once I sorted a replacement it was a lot better. Trying to get the same psi ranges with the auto at the speed and rev ranges suggested for installing the dawes valve was very difficult because of the Auto trans and how at 100 it sits in the low 2000 rpm range (2100-2200 there abouts instead of what the manuals sit at 2600-2700 maybe?), hope you figure it out soon, maybe double check its all plumbed correctly with no leaks.

On a flat road with cruise on my boost will sit at 4-6psi at 100k's with the auto, but rises quite easily with an incline or a bit of load.

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Mine is an auto and sits on about 12 @ 100kph,, max boost is around 20 psi.

Quote:

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Originally Posted by threedogs

Mine is an auto and sits on about 12 @ 100kph,, max boost is around 20 psi.

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Hmm maybe I have it wrong, did read others saying the auto was really hard to get the same boost levels as the manuals at 100 kph(10-12psi), due to the differences in the rpm that each are at while cruising at 100 kph.

I can only get 14psi max boost without going into limp mode, so maybe that has something to do with it also, and not sure if you have a torque converter lockup mod and if that would change the psi readings as engine revving higher 100kph or if the DP chip helps with higher boost levels?

Is your EGR blocked. Transmission is stock no mods as my Auto guy advised not to do it with a daily driver.
IMO my Patrol fly's I know it blows 3ltr Hilux's to the weeds[late models]

Yes EGR is blocked, kinda thought that when I did block it that it is what made my limp mode problems above 14psi boost? but figured the benefits outweighed than not doing it?

You may have other problems causing the limp mode.
have you disconnected the battery to re-set the ECU
Just doesn't sound right , wait till Mudski comes on board
he may be able to diagnose it better,
have you fitted a needle valve ?
Go easy stretching the spring its a bit harder to "un" stretch.
some times SS washers are more accurate

Yes re set ECU a few times, changed MAFs, been testing and testing, tinkering and making small changes, been keeping the allen key for the needle valve and a couple of open ended spanners for dawes valve to make adjustments, kinda think its running pretty good at 14psi and spooling up around 1600rpm, ended up at 14psi after doing some late night cold air runs as noticed that seemed to make a difference, for example on a warmer day could run higher boost but would hit limp with those higher boost levels at night when air temp was colder, so decided to set it up for cooler air temps and seemed to work.

EGT's seem good at 330-350c at 100kph on flat road with cruise on and can rise and drop from there pending hills, seems to be running well now and reasonable power for a 3L(a lot better than the ZD30 in the 03 Navara), fuel economy is around the 12L-100km's with mixture of town and highway driving and just returned today after filling up 12.42L per 100k's with 50% town 40% highway and 10% 4wd driving from full tanks including Sub tank to only a quarter left in main, which was better than I thought it would be.

To be honest I don't think I can get it running any better unless I do further mods like the HPD airbox lid and MAF housing or chip and am pretty happy with where it is at atm, although in comparison it seems there could be room for improvement but also a little done with it and at the stage where I'm just enjoying driving it.

each set up is different as you know, just enjoy as it is. if in doubt go get it Dynoed.
But would hate to get a Dyno and find out I was half a turn off max performance GGRRrrrrrr

Have you checked your intercooler for leaks? Oil deposits on the underside of the ic is a tell tale sign of leaks. Might not be the issue but worth a check. The oem ic's are hopeless and known to leak.

Ok so bit of a late update. I have fitted the needle valve but still have issues. if I fiddle with the needle valve I can get it to boost up to 15-20 but quicker than wanted. As soon as it hits a decent boost level like 15+psi it immediately drops to back to 10 and that's it. At 2800 rpm im still at 5psi and get to 10 at about 3500 so it goes back to the same issues as if the needle valve isn't connected...... Whats happening????? Whats the best way to test the spool up with the needle valve in an auto?
Heres a few pics of my slapped together install to try and see why I have issues
http://i100.photobucket.com/albums/m...230_210935.jpg
http://i100.photobucket.com/albums/m...230_210951.jpg
http://i100.photobucket.com/albums/m...230_211001.jpg
http://i100.photobucket.com/albums/m...230_211009.jpg

The second pic doesnt look right. Can you tell me where the vac line with the dampener on it is coming from?

Comes from the vac pump. Right side of tee as you look at is is from the needle valve and the left side goes to dawes

Acceleration video
http://i100.photobucket.com/albums/m...31_1928281.mp4

Cruising at 100 vid
http://i100.photobucket.com/albums/m...101_173046.mp4

I would probable put a few more pounds of boost in it. Maybe spike at 17psi
What are the temps in "F" or "C",,, If they are Centigrade figures it will support
my more boost required comment ,,,Can tell its an auto too.

I think Mark needs to write up a thread of what is expected from the needle valve
in english, sometimes a lot is lost in translation

Do you have all three blocked at the air solenoid near the airbox

Thats the old style Dawes you have too, without the new heavy spring, I believe. Have you changed the spring? Now going by the vids, without sound on, your not getting boost, even when you floor it. So it could be A : Wind in the Dawes more, B : Wind in the needle valve more, C : Your needle valve is cactus and leaking, or D : you have a boost leak. E : Your Maf is playing up
D is imperative that there is no boost leaks. If you do it will be near impossible to reach and hold boost.
Try this and start from scratch...
Start the car up and wind your needle valve right in to shut off the vacuum flow, you will notice the rod on the VNT arm actuator will go upwards and into the diaphragm. Then will still running open up the needle valve until the rod drops around 10mm. Take the car for a spin. If your boost climbs real slow, wind the needle valve in a little more, if it climbs real fast, open it up. Depending on what brand needle valve you have will depend on how much you need to adjust the needle valve, most of the cheapies need a few turns as they don't have a fine adjustment which is needed for this process. Plus they are prone to leaking too, which is a waste of time to try and adjust then.
Sorry lets get back on track... If the boost climbs good but you don't have the desired boost level (too low boost), wind in the Dawes until you do. Or wind out if its too high. Once the boost level is set, you shouldn't need to touch the Dawes again, only the needle valve you need to fine tune. This can be hit and miss, I have done a few cars now and on some it was pot luck and got it straight away, and some weren't so lucky and it took a few hours to get it right.
With setting your cruise boost too, its all relative to what max boost you run. Everyone says 10psi at 100k's. Yes this is good for a 15-18psi max boost. Anything higher and you need to go higher on your cruise boost because if you don't, your EGT's will be shite, your boost rise will be too slow and you will have power loss. I run 25psi max boost and it sits around 16psi on the highway, give or take a psi. EGT's at 100K's on a flat road will be around 220c. I tried to lower my cruise boost by opening the needle valve and all I did was make my EGTs hit the mid 300's and the car went like a sack of you know what.
The MAF can only be resolved with another known working unit. I had a fella come to me after fitting the NAD's and the car just wouldn't go. I took it for a spin and from around 1500rpm it was guttless, NOT limp mode, just like I was towing something real heavy. We tried the maf from my car and all was good! There is s thread somewhere on how to test the voltages of your maf with a DMM... If you can get a hold of another MAF to try, then do it, just to take it out of the equation.
But don't just look at your intake system on the car for boost leaks and say she's right mate. Not saying that you do/ are, I have been the end of the blame stick from many people who don't check this properly and say its kit they bought is faulty. Thoroughly check, by removing the IC, if theres any oil on the underside, if more than likely leaking, if there isn't, seal it up and dunk it in water and get some air into it with a bike pump to see if any bubbles come out. If there isn't, check all hoses for splits or cracks, if there isn't, make sure all hose clamps are good and can be done up tight, effing tight, if they can? Your intake system is good to go sir!

Hope this helps.

another point I'd like to make is use constant pressure hose clamps, they are a bit more $$$ wise but worth it IMO
OE clamps are shite