ZD30DDTi (non-CRD) in 2000 Patrol suddenly dies & won't restart

...as preface, apart from being mechanic, I'm also an electronics technician, and that said... I only got involved with this repair once I realized the actual problem was purely electronic, not so much a mechanical one....(but obviously there's a bit of tool work involved to get this job done)...

....shorted pins 1 & 8 on the (faux) OBD2 connector to get the MIL light to blink out DTC 0703 -- injector pump communication problem, loom checks out good from pump to ECU, so not there ~ and I'll guess everyone has some idea of how much a replacement pump is...(plus labor for removal/refitting)....

....find out it's fitted with a vp44 EDC pump, do a little research on the matter, and come across this doc ~ http://www.autoelektronika.co.rs/Eng...044%20pump.doc ..... oh goody, so it's a measly $5 worth of electronic components at the crux of the fault! Awesome, right in my ballpark...

..so yeah, remove vp44 from engine (-not- much fun), pull the EDC lid off, confirm the fault and rework the electronics ~ and I'm reasonably confident the pump is now fixed (bad components replaced, but you can't be absolutely sure the other components on the hybrid PCB have survived) ....find out for sure when I refit it (more non-fun) in the next day or 3....I may even post back to confirm it's fixed...

Point of this post? Well, don't be forking out $$$$$$ for a new/reco injector pump on fault 0703, as 95% of the time it's not the pump perse ... it's just the EDC electronics have failed. Hope this saves someone a few grand....

..well, close ... but no cigar...now I've got a zd30 that starts but won't run ...that is, it'll start, come up to idle for a few seconds, and then fall into a knuckling state of overfuel (or perhaps over advance), so you shut it down again before it hydraulics itself to death...

..the rework of the EDC electronics would appear to be successful however ~ DTC0703 was cleared from ECU, the 0505 'all good' DTC comes back after DTC clear, IGN off and on again, crank for 2seconds and reread diagnostics yields '55' every single time, so as far as the ECU is concerned, communications with the pump have been restored, and there are *NO* faults what-so-ever...at least, at the surface level of the OBD system used, not sure if the Nissan software can dig deeper into the (now) problem... I was even able to ascertain the pump is responding to TPS position as well, so it would appear the pump control is all back online as it were, even the furl shutoff solenoid works (praise be to gratis) but something else is awry...

..exactly what, is a mystery to me...perhaps there's a mechanical failure in the valve train of the pump, under the servo control, that's had an oops and caused the original fault, or maybe the EDC mistakenly thinks the TPS value it >last< saw before breakdown, is now the new fuel number to provide at idle (which isn't going to work, as owner reports doing 70kph and just depressing the accelerator to ascend a hill when it cut-out ...never going to idle with that much fuel =)....my electronics skills tell me, the pump may well need recalibration *anyway* just due to slight differences wrt the replacement components...but I don't have a diesel pump test rig laying around...

...end of the day though, it was worth a shot ... and being a zd30 with 200,000k on the clock, the only other kind of shot it's worth, is to be line bored with an armor piercing 50cal round....inlet tract is full of EGR gunk, which is leaking out the ends of the I/C of course, when pulling it over by hand to bring up timing, I noticed cylinder compressions' are all over the place (one pot being way down on the rest), and when I saw the teeth on the can chain drive sprocket all bent, I have no trouble imagining what state the cylinder head is in --- this is not a candidate motor for repair ... this is an engine needing total rebuild (or absolute replacement)...what a horrorshow....

I'm imagining the owner is going to get rid of the vehicle 'as is' ....with a zd30 that 'starts but will not run' fault, and not a DTC to be seen from ECU ... a VGC 7seat patrol let down by the mess that is a zd30... hopefully someone will pick it up for a song, stick an LS1 in it (anything would be better), and end up with a good 4WD.

Bottom line -- reworking the EDC electronics is feasible & doable, but success with fixing the electronics does not guarantee you'll end up with a correctly working injection pump. I was hoping to bring a more definitive answer to the forum regarding 'fixing' the vp44 injection pump, however all I can vouch for is that such a rework of the electronics fixes DTC0703, and the pump ostensibly seems to work again .... but that is all I can attest to ; pump may have other issues.

..first (and last) zd30 I ever go near....

Yes, it does sound like a round (or even 1/2 a belt) of .50 from one of Mr Brownings' finest is needed.
Won't fix it but sure would be satisfying...

Thanks for the post and link, lots of valuable info there for people

Hola solder.... Caught up with you in another thread ... I had 2 years of back seat VP44 mind feck ...and still in saga ...anyhow I read on many UK eBay VP44 FPCM repair sites some time ago that they clearly state ...if your car starts then it's not the FPCM. My truck always started then went into limp and knocked like hell and smoked like there was in fact a cigar ...excuse the pun.

So my Bosch chappie.... non Nissan goto .... once he got my pump stated ....

It's not good news on the pump (what else are they likely to state) ... It needs a housing and advance piston, control unit and both solenoid along with seal kits some screws and clamps so the pump would come in at 1300 plus 17gst. The advance piston and housing were scored up and the control unit had low resistance, the fuel control solenoid also fell to bits when they took it out the pump ...so def issues with the pump.

Needless to say the car started and the pump was not in good shape. I have a terrano with same engine in the paddock that works fine besides failed worthiness test and dead clutch ... Thought of using pump in my Patrol tho everyone said too hard from software perspective. so you may know where I am at with other thread.

If you login to eBay.co.uk there a dealer in Lithuania that sells parts for these pumps at approx 70uod for piston etc. So if you bored over cams and like machano challenge the. Just maybe you could dissemble ur pump and repair cheap if u think it is the pump.

All the very best for the new year

Quote:

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Originally Posted by 808grim

Hola solder.... Caught up with you in another thread ... I had 2 years of back seat VP44 mind feck ...and still in saga ...anyhow I read on many UK eBay VP44 FPCM repair sites some time ago that they clearly state ...if your car starts then it's not the FPCM. My truck always started then went into limp and knocked like hell and smoked like there was in fact a cigar ...excuse the pun.

So my Bosch chappie.... non Nissan goto .... once he got my pump stated ....

It's not good news on the pump (what else are they likely to state) ... It needs a housing and advance piston, control unit and both solenoid along with seal kits some screws and clamps so the pump would come in at 1300 plus 17gst. The advance piston and housing were scored up and the control unit had low resistance, the fuel control solenoid also fell to bits when they took it out the pump ...so def issues with the pump.

Needless to say the car started and the pump was not in good shape. I have a terrano with same engine in the paddock that works fine besides failed worthiness test and dead clutch ... Thought of using pump in my Patrol tho everyone said too hard from software perspective. so you may know where I am at with other thread.

If you login to eBay.co.uk there a dealer in Lithuania that sells parts for these pumps at approx 70uod for piston etc. So if you bored over cams and like machano challenge the. Just maybe you could dissemble ur pump and repair cheap if u think it is the pump.

All the very best for the new year

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Hi - thanks for the comments, however the good news (for me that is =) is that the owner of the patrol has since sold it 'as is' and so I no longer have to waste braincells ~ sometimes defeat can be sweet <grin>...

...however, for anyone else who wanders into this thread and wonders why it didn't work for me and yet such repair apparently works for others ... one word ; 'climate'...

...apparently in climates where it gets cold enough to snow, on very cold days (and depending on the quality of your fuel), extra loading can be incurred in the mechanics of the pump, which consequently overloads the servo which causes the transistor failure. Obviously, this scenario isn't likely to happen here in Australia anytime soon =)...

...the scenario I was facing, as best I can figure it, is exactly as you describe -- the advance piston/bore are likely scored/worn due to time in service (210,000klm/16years), and it is this wear (or some subsequent breakage caused by wear) that caused the servo over-current situation -- although the electronics are seemingly fixed, the pump has a mechanical issue as well ,,,but oh joy, oh bliss....I don't have to worry about it any more...

All the best for 2018 friend!