ZD30 ... Low boost

[Limmy]

Hi members

Need some advice !

Nissan 2005 GUIV zd30

l have dawes set up , needle valve, egr . etc. My patrol has been running fine last few years. Last week i realised my Boost was lower than usual . I though it was probably need adjustment. I stretched the spring and it was set fine back to normal. A few days later , Im struggling to get over 10Psi , with crap fuel economy. I tried to stretch the spring again. Didn't work , I also ordered some more heavy duty springs, still couldnt get past 10psi.. I tried another Dawes valve, still struggling to reach 10psi. I played around with the needle valve, the actuator level moved .

I'm thinking maybe the wet weather had something to do with it. I couldnt find any obvious boost leaks .

Any ideas guys ?

TIA

Limmy

[trev zd30]

Egr stuck open? Unless it’s blocked that is.
Otherwise check all turbo and intercooler pipework for loose hose clamps, boost gauge lines, intercooler etc for leaks

[Limmy]

EGR blocked. Can I do the soapy water trick to test the lines and pipes. Will it still have boost pressure while it idling so I can test ?

[threedogs]

What intercooler do you have, if its the OE one chances are its leaking.
easy to check if its oily its leaking

[Limmy]

I got a welded intercooler. I did notice a bit of oil around my boost sensor on the intercooler. I got one of those boost gauge adapter's that sandwich between intercooler and boost sensor. Maybe that leaking . I might silicone it

[BillsGU]

Sounds like it could be a vacuum problem to me. Soapy water won't show a vacuum leak. Usually the hoses split in the most difficult to see spot. You will have to check the hoses one at a time.

[mudski]

What intercooler do you have, if its the OE one chances are its leaking.
easy to check if its oily its leaking
^^^^^This...

I got a welded intercooler. I did notice a bit of oil around my boost sensor on the intercooler. I got one of those boost gauge adapter's that sandwich between intercooler and boost sensor. Maybe that leaking . I might silicone it
....and this.
Boost leak 100%.

And no need to stretch the spring in the dawes anymore. This issue was corrected with a stronger spring about 3 years ago. Unless you have one of the older Dawes with the old spring then disregard my comment.

[Limmy]

i had the older one. ive put on another one ( smaller one with ceramic ball ).. Where would the vacumm hoses be located ? Im going to buy new silicone hoses tomorrow. clean my intercooler.

[BillsGU]

Start at the hose connected to the turbo actuator and work back to the vacuum pump located on the front of the engine. Also - there are vacuum hoses connected to solenoids under the intercooler. That was where mine were split.

[Limmy]

I think i may have found the problem. While i was replacing all the lines with new silcone ones. i was removing old line from the " boost gauge inline filter " i notice it had a crack and split apart a bit when i pull it. It has some black soot in between the joins. I blew air and it definately is leaking.

Hope that is the main problem ! im ordering another filter

keep you posted !

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