Help - very Rough idle on 4.5Ltr Petrol GU (mostly warm starts)

[SteveWhittam]

My 1999 GU 4.5 litre petrol has been starting rough for a few months and is getting worse
I live in Brisbane so its never really cold.
Last Summer I had a similar problem , then over winter it went away (mornings about 12-14 degrees)
Now we are back in summer so a cold morning first start from say engine temp 22-28 degrees - its running with a really rough idle for about 5-10 seconds then it seems to clear and the revs lift and all is good
I don't know if its a sensor somewhere, or a fuel pressure thing.
I'm reluctant to take it to my local Nissan Dealer before getting some advice from Patrol enthusiasts like yourselves

[mudski]

Id be going through all the usual and easiest on a petty motor first. Plugs, leads, coil/s etc etc. When was the last time any of these were changed?

[SteveWhittam]

Thanks Mudski
I'v done that (Except the Coil) New NGK Iridium plugs and New leads about 6 months ago
Could the coil do that?
Cause later in the day it seems to start up just fine

[jff45]

Maybe check for fault codes to see if there's an issue with any sensors

[Brisey]

My 4.8 was running rough after the motor warmed up & was good when it cooled down a bit. It ended up being a coil pack was breaking down with heat. It wasn't showing any codes.

Cheers
Bri