Dump pipe gasket blew out, now code 0707

[Beanbolta]

Hey fellas,

I'm about 1600 km into a rebuilt DI zd30 in my '02 GU so forgive me in advance if I seem a bit anxious! In case you wondered I made a huge little mistake on my first oil change (done by yours truely), where my mechanic guesses I didn't click the canister into the aluminium housing properly, causing it to get crushed when I screwed it onto the engine which starved it of oil for the 1500km before the S hit the F. As for the rebuild, we reused the crank, cam shaft, valves and injector pump. Everything else was toast, so don't do that! Couple other possibly relevant details before I get into it is that it's auto and has Dawes and EGR block fitted.

SO, on a recent drive i started noticing the the turbo was spooling abnormally high for such low throttle and rpms, as evidenced by the full wastegate whistle when I let off the throttle below 2.5k rpm. It started having power issues so pulled over and discovered soot on the inside of the turbo heat shield. Continued on home in ultra-baby mode trying not to get on boost. Exhaust noise got progressively louder, power loss was very apparent and it would occasionally lose all power and drop to idle rpm for a second or two. Eventually check engine light came on while going up a hill.

Pulled off the heat shield when I got home and turns out one of the dump studs completely fell out, other 2 nuts were loose and the gasket was missing a piece (we reused the old one btw). Fast forward to today, fitted a new gasket and replaced the missing stud, however the symptoms haven't changed.

It idles just fine and under 2k rpm is reasonably smooth but anything above that or say 15% throttle and it gets a bit unhappy - revs jump up and down, or to idle for a second.. Check engine light doesnt come on unless i persist on the throttle (being gentle) while it's under load like going up a hill. I pulled the codes but I accidentally cleared them after realising I was reading the digits backwards and started again. Can't get 0707 wrong through, indicating an injector pump issue. I recall one with 4 as the second digit, could have been the one for the IP spill valve, IP fuel cutout or ECU. (0704, 1004, 0804, respectively), anybody's guess though.

Could the gasket and code 0707 be related or should I start down the path for troubleshooting the injector pump (from what ive read; potentially dying IP, air in the line - bad primer diaphragm, or just bad fuel filter, orrr dirty MAF.. etc)? I haven't driven it since clearing the codes but somehow I don't think anything will have changed since doing that. Would hate for the IP to be going out so soon after a full rebuild, that is for sure, but it does seem very coincidental.

I'll be seeing my mechanic who I rebuilt the engine with soon but I'd love to see what you guys reckon In the meantime. Thanks for reading

[Turtle_au]

Drive it around then check codes again.
Time to invest in a scanner, it can also display realtime values and save a log file.
I got this one, links to NDS1 app on my android devices.
http://www.buyobd.com/index.php?main...&products_id=2

Sent from my SM-T355Y using Tapatalk

[Beanbolta]

That is one cool device Turtle, never even considered that bluetooth OBD scanners were a thing, but of course they are. And so cheap! Will definitely be looking into that in the future.

That aside, seems I was right to be anxious. The error code 0707 returned (on its own) and I managed to see my mechanic today, he called up an injection specialist he knows and described the symptoms to him, and the dude thinks my injector pump is basically toast. I can still putter around as long as I stay on very low rpms since boost = bad, but will have to replace/rebuild it quite soon, by the sounds of it. He said with the km on it it's getting to that age, but something else which makes no sense to me is that he thinks my accidentally driving through a very large puddle at 60 (as in couldn't see it covering the road) may also have something to do with it, and that apparently the 2 wires which go into the IP and control the injection timing have the potential to short out (hence error code 0707). Seems like a pretty fundamental flaw to me if true, and one which I am certain Nissan wouldn't leave there, because patrols (pre '10 at least!) are basically built for offroading! Not sure what detail I'm missing there but there is no way something mounted so low on the engine (in comparison to, say, the fuse box) would have the ability to be shorted out. Not like I'm the first guy in a patrol to get water up in the engine bay, nor are they notorious (as far as I'm aware) for f***ing up when you drive through deep water or splash it up under the bonnet.