Gt-r Engine Problem

[DSF]

G'Day Skyline Guru's,

I am calling upon your collective expertise to help in a problem I have with my car. Firstly I would like to apologise for the long winded post, but want to make sure I include as much information as possible to aid in the fault finding. Secondly I will admit that my mechanical knowledge is very limited and my own resources after the same (i.e. basic tools with limited spare in my garage). To start with I will give details of what I know of my car and when this problem first started, its a 1989 R32 GT-R imported by Autoworx that is in standard condition except the following;

* Nismo 240km/hr speedo

* Cat back exhaust

* Pod filters

* Twin plate clutch

* Aftermarket suspension

* Greddy boost and temperature gauge and a Delphi head up display unit.

I was heading home when I was about to turn onto a 100km zone stretch of road. I thought to myself that giving the car a bit of stick up to the speed limit won't hurt, so I gassed the pedal in 2nd gear. The revs were at roughly 5500rpm when I heard a backfire and the engine started to stall. I managed to coast the car most of the way home with the engine not wanting to exceed 2000rpm at any stage. Luckily I lived not to far from when this incident happened (1km max distance) so once I parked the car I pondered on the extent of damage I had done. The next day I cruised the car to the local servo mechanic (again only 250 metres away) were he tested the car to the best of his abilities. His limited findings were that compression in all cylinders were good and the engine oil and coolant were not fouled (meaning no blown gaskets). He said that the battery needed changing so I got that replaced straight away but other than that he had no idea about these types of cars. A certain import store with a so called GT-R specialist (which I will not defame) was recommended to me for the repair of my car, so I organised for the car to be trucked to them with details of what had happened. Anyway to make a long story short I received my car back after 9 days with the GT-R specialist saying that he doesn't know how to fix it (this is after paying a considerable amount of money for his expertise). So the car has been parked in my garage ever since awaiting repairs.

These are the known symptoms;

Engine idles smoothly but if you try to free rev it will climb to 4500rpm than just after that it will stall back to a rough idle for a few seconds before regaining a smooth idle. It is hard to tell if the turbo's are boosting but there is needle deflection from the boost gauge.

Trying to drive the car it will not exceed 2500rpm and the engine wants to stall and stutter continuously. If the battery is disconnected and all power is drained, upon reconnection the car drives as normal for a period of no more than 30 seconds.

The engine appears to be over fuelling as there is copious amounts of black soot/unburnt fuel than there was before this problem. Again there are no unusual sounds coming from the engine and the temperature remains normal.

Before all of this the car was a dream to drive with the only hiccup being a very infrequent engine stall during low speed cruising.

Here is a list of all the things that have been carried out to try and fault find the source of the problem:

* ECU code checked with nil faults found (I used the guide on this forum).

* Removed than replaced boost gauge and Head up display with nil change in performance.

* Swapped and replaced AFM's with nil change.

* Replaced and gapped spark plugs (another guide located on this forum).

* Replaced fuel pump with a new item and carried out the earth wire and positive wire mod including installing a relay (again I used a guide on this forum).

* Replaced all vacuum hoses were possible.

* Checked timing, it advances during revving until the 4000-4500rpm mark were it goes all over the place than retards itself.

* Checked all wiring at the ECU and in the engine compartment, including rearrangement of the ground wiring kit.

* Removed majority of inlet pipe work then cleaned and refitted securely.

* Removed coil packs and mega-ohm the casings to check for current leakage.

* Fiddled with the TBC to see if that was a contributing factor, as yet I am undecided due to the limited rev range.

* Disconnected exhaust at turbo's to check for no blockages in cat converter (this was done buy the GT-R specialist so I doubt its authenticity)

* Disconnected O2 sensors to confirm operation (again it was supposedly done by the GT-R expert)

* Swapped over ECU and AFM's were known serviceable items (you guessed it, done by the GT-R specialist so I have no idea if it was really carried out).

* I have even tried praying to God All Mighty, Allah, Vishnu and Buddha (not necessarily in that order) to see if any of them are just jerking my chain, but alas to no avail.

I have conversed with a member of this forum and he has suggested that it is a turbo failure. I believe that this is more then likely the end scenario but am hoping that it might be something simple I can fix (coil packs, leaking pipes or wiring that I have missed). Or if possible is there anyone in the Newcastle area willing to help in further diagnosis/repair, I would be much appreciative (i.e. offering alcohol, money or eternal praise). As the time has come when my wife is totally annoyed with the car sitting in the garage and she wants it gone. I hope to repair the car before I sell it just to take it for that last drive, but if not I will be forced to sell the car as is.

[donkey]

hey there, check 'nightman' post, "missfire@5000rpm" about hairline crack in coil. spark jumping etc.......hope this may help.......

[SLIPPERY]

No, see other thread. Coil pack issues dont affect driveability this much

CLOSE this thread mods

[bubba]

The immediate symptoms sound like a popped cooler hose..

[Beer Baron]

yep, the first thing I would do is double check all the piping from turbos to cooler and from cooler to plenum.

[infamous_t]

  bubba said:

The immediate symptoms sound like a popped cooler hose..

x2

But the latter symptoms sound like spark is being killed,

• wether by bad coilpacks,
  
• failing/wrongly gapped sparkplugs,
  
• damaged electical loom (either ecu, or injector loom),
  
• also there are seals that can fail allowing oil into coilpack/sparkplug housing - this one was my problem
  

[Guilt-Toy]

hey mate.

I should be able to help you.

Il PM you my details and we can see what we can do.

[nizmonut]

check the mechanical timing, i found once on mine after booting it the cam belt skipped a few teeth and wouldnt climb over 2500. due to the exhaust suddenley been so retarded.