Fitting wiring loom VG30DETT

300ZX
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Initial Z
Posts: 49
Location: Christchurch

Fitting wiring loom VG30DETT

Post by Initial Z » Sun Sep 16, 2012 7:30 pm

Hey guys, today i finaly got my engine in the hole after a very clean engine bay respray. came up great!
only thing i had trouble with was getting the loom plugs through the bulkhead and down to the ecu.
At first i took some advice from project z and cut my old loom to pull it out,
then destroy the clamping plate with a hammer and chizel. that was the easy part,
but take my advice and just pull the passengers side of the dash apart.
i tried the so called Easy way, but there was no way in hell i could get the plugs to go
all the way down with the a/c heater unit hard up against the firewall.
after cursing at it for 15 minutes i decided to pull the dash apart,
5 minutes of striping it down i had the plugs in place and connected to the ecu.
do it once do it right, STRIP THE DASH. its honestly easier and faster. :D

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ZILVER
Posts: 470
Location: Auckland

Post by ZILVER » Mon Sep 17, 2012 8:52 am

Easier to install the EFi Harness/loom before dropping the engine back in. The hole through the fire wall can be enlargened slightly with a pry-bar to get the plugs through and then use a rubber mallet to flatten back to shape. Alternativly if you dislike the idea of being somewhat brutal to the Z, de-pinning the plugs would probably have been less time consuming than pulling apart the dash.

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Wed Sep 19, 2012 5:31 pm

hey thanks for input zilver, suprisingly didnt take long to pull apart, i think it was about 8, 10mm bolts & nuts and most of it came away pretty easy,
the harness was still attached to the engine so i had to do it while the engine was swinging from the crane.
now thats it done tho it was realy no major.
cant wait to get her running, do these motors run factory oil coolers?
slightly different line setup from the n/a, wanna get everything setup perfect before i turn the key.
Z32 2+0 TT Project

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ZILVER
Posts: 470
Location: Auckland

Post by ZILVER » Thu Sep 20, 2012 2:11 pm

No problem. I just hate pulling the dash myself - risks breaking tabs/causing squeaks etc.

Factory TT oil cooler is below the air intake box/front of radiator

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Sat Sep 22, 2012 7:46 pm

yea i thought so, bought the engine pretty much bare, so haveto buy everything aftermarket, very hard to find factory bits in chch,
so i will most likely haveto relocate some parts and mount things differently, just going by the inlet and outlets of factory connections
makes it abit of a puzzle, especially when there is twice as many vacuum lines and sensors :? dont kno weither to go for
twin intercoolers, or one big one with twin inlets and outlets. far too many options.
Z32 2+0 TT Project

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ZILVER
Posts: 470
Location: Auckland

Post by ZILVER » Tue Feb 12, 2013 4:06 pm

Hows it all going? - Any updates?
Club mates should have a great source of spare parts. A wanted add usually yields results.

I mass import new parts too (specifically for Z32/Z33/Z34) for club mates. If you want a good discounted rate then feel free to contact me as I maybe able to help further.

As for your intercooler options - I'd personally recommend keeping with the twin/side mounted intercoolers rather than a single front mounted type. Front Mounted types will decrease cool airflow to the radiator and engine bay - greater potential for overheating.

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Fri Feb 15, 2013 8:56 pm

Hey Zilver, i decided to go for a front mounted intercooler, but its one of the small ones that lean forward so
cool air should still make its way through, i went with a tripple core alloy radiator with a large electric fan
to keep water temps in check. i also side mounted a 10 row oil cooler so the intercooler would not block its
natural air flow. Long story short its very close to being done, only thing is i cant get her to start.
shes full of fuel (after fixing a very bad fuel leak) and seems to have spark as it has
the odd put like it wants to start. Any ideas? i have pulled the front 4 spark plugs out and
they seem to be in ok condition, will only pull the rears if i haveto as you kno they are
abit harder to get too. any feedback would be great. Cheers
Z32 2+0 TT Project

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Fri Feb 15, 2013 9:31 pm

one other thing, the plugs werent wet when i pulled them. i dont have alot of experience with
these motors, are they usualy wet when the vehicle had been turned over a few times without firing?
they were abit black and sooty but no actual liquid.
the vehicle ran fine with the old n/a engine so it must be something on this
tt engine not the vehicle itself, maybe a new power transistor unit?
Z32 2+0 TT Project

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djz
Posts: 849
Location: Christchurch

Post by djz » Sat Feb 16, 2013 8:53 am

I don't know much about VGs but it sounds like you don't have fuel, does the pump prime when you turn the key on?
Nissan 280ZX 2 seater RB26 powered.

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Sat Feb 16, 2013 10:27 am

yea nothing wrong with fuel delivery, i pulled off the feed line after the fuel filter and
it was super presurized. covered half the engine in fuel, so im thinking either the fuel dampener
may not be opening letting fuel into the rail, or possibly dodgy injectors?
i have rulled out spark as i have tested it and it has a good spark everytime.
i ran a diagnostics test and it comes up code 55 everytime indicating no electrical error.
This is realy starting to piss me off. ive tried almost everything i can think of,
except for tow starting it but thats gonna be my last resort lol.
surely someone has some solid vg30dett experience that can help. cheers
Z32 2+0 TT Project

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ZILVER
Posts: 470
Location: Auckland

Post by ZILVER » Sat Feb 16, 2013 11:03 am

Tell us about your fuel injectors (original) connectors? and if you have a custom ECU

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Sat Feb 16, 2013 1:19 pm

original connectors, square type brittle ones, visualy they havent been touched before
because covers and connectors are still in tact, so they are probably the original
injectors aswell, 23 years old. i have spent all morning inspecting different wee things
and everytime it seems to be either the ecu is telling the injectors not to spray,
or all 6 injectors are F#$%ED which i find very unlikely. ecu is factory but it has been
chiped/tuned to remove the factory speed cut, fuel cut and all that kindof crap.
i used a test light to check injectors for power and they constantly have power
so the injector loom must be fine. i realy dont want to do a plenum pull unless
im certain that its neccesary. is there any hidden fuses or relays for injectors that arent in
your usual easy to see place? eg. engine bay box, drivers side box, and drivers kick panel box?
i have checked all 3 of these and they are all good.
Z32 2+0 TT Project

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ZILVER
Posts: 470
Location: Auckland

Post by ZILVER » Sat Feb 16, 2013 5:16 pm

Well ruling out fuel for now. I cant troubleshoot without knowing more.

A PTU failure I think may not necessarily registered an error code with the ECU diagnostic. Did you get the PTU with the engine?
I've never heard of one completly fail without causing issues first whilst car is running first. But I know a PTU failure typically means no spark irregardless of the injector pulse. Can you check this connection or borrow/get another PTU to test?

Did the ECU come with the TT engine?

Starter not engaging? If not the starter relay behind the fender is probably the only one you havnt checked?

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Sat Feb 16, 2013 5:53 pm

Starter engages fine, as I said it putts every now and then indicating
That atleast one cylinder is igniting something, it just doeznt get
Enough fuel to complete a full cycle. I will try starting it with some
Starting solvent when I get back to work during the week.
If it starts either cold start is not working or injectors will havto come out.
Ptu and ecu came with motor, but ptu is the newer plastic
Housing type, not the older aluminium type so im pretty sure its good.
Spark is fine, fuel circulation is fine, but combustion chamber
Is dry.
Z32 2+0 TT Project

Initial Z
Posts: 49
Location: Christchurch

Post by Initial Z » Sat Feb 16, 2013 8:39 pm

Injectors were the issue, got her to run fine on the lpg tank
From my bbq. plenum pulled out now and injectors are
Blocked. Might just replace em all for good measure.
Thanks for the help fellaz. Appreciate it.
Last edited by Initial Z on Sun Feb 17, 2013 7:24 pm, edited 1 time in total.
Z32 2+0 TT Project

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