HR30 Skyline - running rough after being in storage

[tpbftw]

HR30 Skyline - running rough after being in storage

hey guys, hoping someone here can point me in the right direction....

100% stock standard 1982 Nissan Skyline HR30 – L20ET. Was running perfectly fine as a daily driver until put into storage January 2014. Unfortunately I neglected to put in a fuel stabiliser, but did leave the battery on an automatic charger. 

Around 18 months later in mid 2015 I started it, maybe put in some new fuel, maybe not, drove it around for a week then put it back into storage, was running fine.

Fast forward another 18 months and I’m back in the country permanently now and looking to return it to a daily driver, I hopped in and cranked it, battery has heaps of cranking power, but the engine didn’t want to fire, gave it a little more throttle than normal and it ran with the engine shaking like an unbalanced washing machine for around 10-20 seconds before I turned it off.

Next I drained the fuel tank, replaced with 20L of 95 octane fuel, replaced fuel filter, then tried again. Engine no longer shaking and but sounds like running on 4 or 5 cylinders. I can now hear the old fuel pump running almost constantly – it never used to do this.

Replaced fuel pump with new Bosch pump from NZEFI, looks identical to stock. Still running rough, new fuel pump running almost constantly.

Cleaned fuel injectors using this method: https://www.youtube.com/watch?v=rUUgR94drxg
- this seemed to get it idling a bit better (engine was cold), and at first I thought I had fixed it, could rev it freely when it was cold.

However after a couple minutes of idling and warming up (still sounds like on 5 cylinders) when I give it 1/3rd throttle or more it will hesitate and cut in and out. If I persist with trying to rev it, sometimes it will hesitate, cut out, cut back in then rev nearly freely up to 4000rpm or so. If I try and drive down the street, under 1/3rd throttle or more it will surge violently, cut in and out, if I back off the throttle I can drive it at around 30-40kph but its pretty temperamental.

Next I put in new spark plugs and leads, same symptoms.

Next replaced the AFM with second hand one, disconnected battery, stood on brakes, reconnected battery, same symptoms. Then I took the black cover off and turned it counter clockwise 5-10 clicks to richen the mixture. This seemed to get it to run a little bit better, but after a couple of laps around the block it was back to surging / cutting in and out.

I’ve had a look around general wiring, pulled plugs off and used contact cleaner. Pulled the distributor off, looks fine, the gears at the bottom which I think is the Camshaft Angle Sensor look fine.



Not sure what to do next, what do these symptoms sound like to you? It seems like it gets worse as the car warms up.

As a side note, after installing the second hand AFM now the temperature gauge goes to above hot as soon as you turn on the ignition.