Check engine light

Hi all , bought a 2002 3.0 Patrol wagon 4 months ago , intermittently the check engine light comes of with varying degrees of power loss , goes great for 2-3 weeks then plays up , when it's going well it flies but when it plays up it barely pulls its own weight along , no rhyme or reason to it - rough rds or freeway . Have replaced MAF sensor , cleaned ALL earth leads , removed battery leads for a few hrs , changed 3 fuel filters - 1st 1 had a tiny bit of water in it but last 2 fine . Put scan tool on & brings up P7 fuel injection feedback . Local fuel injection mob want to put a pump on it but I'm not convinced & at $3000 I want to be sure . Im told a few different things will bring up that fault code ? Any help welcome as I'm close to burning the thing .

one of my mates had a problem with no power and gutless on his,it ended up being a fuel sensor somewhere on it..700-800 bucks I think he said...goes like a shower of shit no....hopefully someone who knows a bit more will chime in soon..i'll ring him later and try and find out for sure

Thanks mate , the intermittent thing has got me , if the pump is that stuffed it'll barely pull itself along - I can't imagine it'd come good for weeks & go like a shower of shit . I believe the pump 'talks' to the crank sensor , so maybe that sensor is crook ? & im told the 'PNP' switch ( whatever that is ) on the gearbox can play up & give the same symptoms I've got ? They tell me the gearbox sensor is under $50 so I'll get 1 tomora & I'll look into the crank sensor price aswell , been a process of elimination so far ...

These are usually results of fuel starvation/air in the fuel/bad fuel. So long you have none of those then it is the pump and eventually it will give up on you.

If you can monitor/observe ICV% via ECUTalk interface/software (worth every cent) when it goes pear shaped you can then check for air in fuel for example.

There is no easy fix if it is internal electronics problem and Bosch/Zexel VP44 IP is well know for these failures. The trouble is that sensors are not exactly easily replaceable and most Diesel Injection specialists are encouraged to change over the pump as it is much simpler for them. If you can find specialist willing to check/strip and fix the unfixable (broken pump controller PCB connections) you will still pay handsomely.

My take is unless you are desperate you can source change over pump from Baileys Diesel group for around $2,000, trouble is you still need to fit it which is the headache too.

If you are going to fit replacement pump consider fitting external lift pump as well.

PN (park/neutral switch) is another symptom but doesn't generate Injection pump code and usually manifest itself with trouble getting it revved up past certain RPM.

Easily checked by starting the engine and hitting heat/fast idle switch, RPMs should raise to 1,100, selecting a gear should drop them back to low idle (750 RPM)as you move the lever from Neutral.

Regards

read through this sprock
http://www.nissanpatrol.com.au/forum...ent-Power-Loss
hope it helps

Thanks Rumcajs , yeah it idles up with heat switch on but cuts back when put it into drive so I assume it's not that then 😩 , thanks WA489 , just read that 5 mins ago - I've been trawling the forum for anything remotely related to my problem . IF the pump is the problem has anyone heard of them playing up as bad as mine but then coming good for a few weeks then playing up again for a day or so & so on & so on ?

Yes they can play up for a while.

Anyway you need to eliminate the possibilities and then decide. Methodical approach is required.

See diagnostic procedures bellow:

Thank for that , hope it's not the pump but we'll see - if it gets to that it'll be a job for someone else , I don't have the time or patience to pull it apart but mainly the time factor . Thanks again - more process of elimination tomorrow- fit clear fuel lines to check for bubbles , replace ALL rubber fuel lines etc . I've had top of tank open ( see earlier thread 'fuel tank issue ) . Tank was spotless however found the metal tray that should be spot welded in the bottom was moving around as much as the spring loaded pickup would allow, removed it from tank as I couldn't weld it in there & didn't see its purpose - I'm told it's a holder for a submersible pump in the petrol Patrols ? . Intermittent problem still persisted 😤

@ RUMCAJS I have Yendors ECU-Talk and the icv% is around 75% most the time,
However I notice when I go away its high when the tanks are full and gets down
to 55% on the way home when tanks are low.
By doing that lift pump mod are you masking a problem???

By lift pump do you mean the primer on top of the filter housing or a seperate unit down near the tank to pressurise the system ?