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Hi fellow patrol owners... went to jump in my bus this arvo..went fora drive and it seems like it won't boost past 2000 rpms...goes up to and 5-7psi then will drop off to nothing.. After 2000rpm it's got no balls... Is this what they call limp mode? Zd30..
hopefully someone with a zd30 can help mate but it sounds like a leak and not holding pressure in my opinion. Check every connection from turbo to inlet manifold.Quote:
Originally Posted by mullet_hunter
See if you can see any carbon deposit on any hose seals too?
Ye if feels like it's leaking boost.. Like when a hose comes off the intercooler.. But it's not blowing any black smoke and hoses look alright... Will need to have a better look over the weekend..
Whats it like prior 2000rpm? Cleaned the maf lately. Could be a boost leak. Condition of the intercooler? Is it oem or aftermarket? Any oil leaking from the intercooler?
Also what about the fuel filter. Last changed? When you get limp mode if you let off the go pedal and back on again it goes away.
Ye it seems if u let off the gas pedal then it will boost to arnd 2000rpm.. then nothing over that... is this what they mean by limp mode.. im just a bit dumb founded how its just happened nw.. been running 27psi befor with no dramas no i cnt get it to boost much over 7 to 10psi...
Mafs clean.. new fuel filter when i done injector pump few weeks back.. will have to have a better look into the weeknd...
Split hose for sure mate.
Ye it drives and feels like the same as if it blows the intercooler hose off but no black smoke.. and hoses and clamps look tight n all in place...
With MR possible hose split or from running big boost split the IC open a bit more.
You can remove the IC and check in water with a bike pump, make sure its dry before you replace
it a hair dryer will help.
At Mudski MH is running a HPD Maf housing, you mentioned a
while back they should eliminate all over boost probs?
How do you stop the limp mode from happening
And have a good look at every hose mate it might look food but moght have a little hole in it
but fitting nads you can control the boost preventing limp or over boost modeQuote:
Originally Posted by shan-747
Ye will take off intercooler piping and hoses and check for any leaks.. it will boost upto 2000rpm but after that it drops off to nothing.. wouldnt be suprised if ive split either a hose or intercooler as i was running pretty high boost at arnd 27psi...
Well I found time to look into why I'm losing boost.. Hoses and pipes looked alright as did intercooler... But thought I'd pull intercooler off to double check and next minute bubbles... Haha well I guess it was gona happen sooner or later running that much boost... Now time to get me a replacement...just gona go with a factory replacement with the end tanks tigged up...
Could you expand on how to do this a bit more please? Need to check my I/C.Quote:
Originally Posted by threedogs
So you remove intercooler... tape up both ends... put it in a tub of water.. then preasurise it using either a bike pump or in my case an air gun making sure to only feather the trigger... then look for bubbles... if its hrd to push dwn into the water and wants to float or u cant see any visible bubbles its good.. or in my case if it bubbles and gets heavy frn water getn inside then shes leaking..lol..
When testing i usually dip the flush taped end dwn into the water first and preasure the bent end up the top that way ur not putting the sensor into the water...
Excellent, thanks mate. Will check mine tonight, fingers crossed it's my problem as well, at least then I know what's going on.
Good luck with ur intercooler mate...i went for a quick drive arnd the block... first time i seen my egts go over 400... so it does go to show that the more boost the lower ur egts...
The hpd housing doesn't eliminate over boost issues. It simply allows you to overboost.Quote:
Originally Posted by threedogs
Good to see the op has found the issue.
Good find MH a factory tigged IC is about 33% bigger than stock, so a small gain to be had.
Have a look at an XR6 IC I think they would be very close to working .
Hi Mudski, what you said above is what's happening to my year 2000 model Patrol. Do you know what is the fix on this problem?Quote:
Originally Posted by mudski
Cheers
thats limp mode mate. Its usually caused by engine overboosting. The zd's ecu has an overboost safety precaution which is usually around the 16psi. Some times giving the maf a clean helps. Or replacing the maf, or fitting a dawes and needle valve. The dawes is designed so you can limit the maximum boost pressure so its below the limp mode over boost threshold.Quote:
Originally Posted by Val
Sent from my SM-P600 using Tapatalk
Thanks mate. I will clean and check MAF sensor then if it is working fine.
Would you be able to send me a copy of Nissan Patrol Reference Document to my email address as I don't have enough post yet to download it? bon2x_77@yahoo.com
Cheers
Val
Thank you for the info Mudsky.
Hi to all,
I want to share what we (me and my electronic engineer) did to fix this limp mode problem that we call without spending a single dollar. Since after checking all the sensors that I know (MAF, Engine TEMP and boost sensor) and proven that they are all working fine, I've tweak few times the variable turbocharger control actuator and that dropping of my boost disappeared. I’ve felt more power on the acceleration now even my boost goes up to 14 psi only.
Yeah thats also done here but for many its a pretty tricky job. Hence using a needle valve. Does the same as what you did but you can adjust it with minutes without touching the actuator. Get more boost into it mate and it will go even better.Quote:
Originally Posted by Val
Cheers.
Mark.
Hi Mudsky,
Thank for the advice mate. I like doing mechanical job (but I'm not experienced yet) so I think if I can get hold off on how to do this dawes and needle valve I will try it one day. How much do you think this dawes and needle valve kit that I need?
Anyone from Bundaberg Queensland in this forum?
Cheers
Val
They're $154 (with EGR plate) plus $12, but member get 10% of the item price... $154 including post without the plate.
Thanks mate. I'll get my boss (wife) to put a budget on this.
Cheers
Bump for Val as post went into moderation due 2 email address.Quote:
Originally Posted by Val
Val, type in "nissan patrol reference document" into google, first listing should be the Nissan patrol reference document hosted on another site that is a downloadable pdf file :)
Fitted new intercooler and rig still wouldn't boost... Pretty sure it's got something to do with vac system... So went and plugd ports at solanoid and setup Dawes and needle valve... But I can't get it to boost over 10psi... Even wiv Dawes valves right in? Bloody pootrol... Thinking of just getn one of them diesel smart actuators set for 24psi... Is anyone on here running one... I think there like 220 or something but have only herd good feedback... It bypasses the whole factory vacuum system altogether...
Pull the dawes apart mate and just check the spring and ball to make sure its ok in there. Double check that all hoses and clamps are on good. Which imsure you have done. Also try winding in the needle valve so its closed totally. See what happens when you go for a drive.
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Ended up getn it to boost... Disconnected battery... Cleaned maf sensor.. Triple checked all hoses and conections... Started bus.. Opened the needle to the actuator arm fell away frm grub screw then adjusted to it went back up n touched the grub screw... Dawes valve is wound right in til there's no more thread... I'm seeing arnd 18psi nw... The 4 inch is sucking in some serious air... And when I turn off the rig it sounds almost like someone's flushing a toilet.. Lol.. Is this normal?
That does not sound normal. Also, you should be able to get more than 18psi boost max. Are you running a different intake pipe?Quote:
Originally Posted by mullet_hunter
I knw the snorkels are suppose to suck air but mine sucks realy hrd.. Like if I block the inlet of my snorkle wiv my hand there's so much preasure there that u can see the whole airbox flex.. Lol.. It won't stall either it just wnts to keep sucking.. Feels and sounds like those vacumes that are used at the servos to clean ur car... If I open up the needle valve the flush noise goes away but then there's lagy spool up rate.. I have hpd maf housing and billet lid and 4 inch snorkle all the way to airbox... Max boost I've seen is 20... Ideally I want to set arnd 24psi... But I've maxed out Dawes valve?
What happens if you run it without the Dawes valve. It's only there to set a ceiling on the boost.
That sound is just because of the larger id snorkel and tge sound is resonating further up the snorkel. The flushing sound via the needle valve is air being sucked through the needle valve back toward the intake. Im not so sure the sound should be something to worry about. Your snorkel is larger, metal and round. The intake sound will be different for sure.
What air filter are you running?
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it use to boost upto 27psi.. (ecu controlled) then it just started boosting to arnd 5psi..and gradually upto 10-15psi... if i would put my foot down boost would drop to 0... really weird.. i thought it must had been leaking intercooler not holding boost so replaced and still same problem.. losing boost.. so thought id go back to manual boost control wiv dawes and needle valve but for some reason the dawes valve is limiting max boost to around 18-20psi... drives good but far from what it use to go like with the higher boost? i guess most would be happy wiv it.. spools and drives hard.. but it feels like it doesn't have the bigger power band it use to have.. its like after it reaches 3000rpm or 18psi it runs out of puff... as before it use to pull hrd in every gear.. egts rarely went over 300-350..
k&n filter...
Is the vacuum hose still running through the vacuum solenoid? Maybe its limiting the boost?
If so, maybe you could try running the hose directly to the needle/dawes valve.