Tricky-Ricky

Yes the fan motor either needs cleaning or replacing, i would not drive it like that as if its only starting when physically moved then it wont be starting when it should so the engine will overheat, as i said get it recovered if you don't want to risk engine problems due to overheating.

Does it just pink at low loads/RPM? or when its being driven hard (detonation)? Have you got any mods? it sounds like you just have some preignition due to low ROM fuel. Was the intended remap from an authorized Up-rev tuner? if not then i would walk away, Up-rev is the only retuning software available for the DE motor.

Its your electric colling fans, if both don't come on when you turn on the air con? if not then you either need to replace them or have them cleaned and refurbed, its not an easy task to do right but can be done DIY, i used to offer a service doing this, i may have a spare fan motor left over from when i did this, i will have a look.

Shame you not in my neck of the woods, i could have sorted it for you for just the price of a coil pack if that what was needed, the insert should be easy to remove and it would just take a suitably shaped nut epoxied in to complete, but not really necessary as the the coil pack would stay put anyway. As for user names, i started out on car forums years ago and because the swear filter wouldn't let me use Tricky-Dicky which is actually what i am called (Richard) in reality, i went with Tricky-Ricky which was the nearest option, so i have just stuck with it.

i would not even try and diagnose an engine noise by a recorded audio file, first hand is the only way to make a sensible comment.

Turn on the air con and look at the fans, if they are not both working then you have a problem, and any slow driving in traffic will cause overheat, every time, get it recovered and sort the fans, anything else and your risking your engine.

The coil pack needs no earth other than the wiring, the thread that the bolt has sheared is actually a brass insert which TBH should not have caused the sheared bolt due to corrosion, i would suspect somebody over tightened it, anyway the insert should be able to be removed carefully and another sealed in with epoxy, as the cam covers are made of plastic. The clamp bodge also sounds suspicious, and could of caused the fault in the first place. The fault may be a a faulty coil pack or simply because the coil pack is actually loose, however i somehow doubt that as the coil pack is a pretty tight fit in the cam cover, i personally whoud be very suspicious, and take it somewhere else, or even fix yourself if you feel able, just by another coil pack and replace the insert.

For starters replace the one way valve in the PCV system, if this is staying partially open it will not only be allowing extra unmeatered air into the intake when not at idle, so causing weak AFRs, it will also suck a lot of oil into the plenum and so get burned.

Somebody start a "what do you love about the 350Z thread" FFS or this will drag on and on.

Oh! i don't know .... going by your old blue Z i would definitely say FAT!

Two reasons...fat and slow!

I basically meant that you had to pay for the license for every car plus the cost of mapping, normally you just pay for the mapping. OK granted you pay for the stand alone ECU but since you already own the ECU with up-rev, your paying the makers of the software for the privilege of being able to have it mapped, so yeah sneaky!

Sneaky American idea by the developers of Up-Rev remapping software, the software can be bought by anyone either private or professional, but each map thats created via the software has to have a license, which means that the developers get revenue for each map done, IE one map + one license fee......wish i had thought of it.

Since Nissan developed the VQ engine series in 1994 and these where developed from the VG series from 1984, and the Nissan Renault alliance occurred in 1999, you could hardly say that they had a hand in it.

The breather hose if its not very rigid will collapse at idle as this is where there is the strongest vacuum, it will reduce with RPM. http://www.ebay.co.uk/sch/i.html?_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xstainless+braided+hose&_nkw=stainless+braided+hose&_sacat=0&_from=R40