Idle issue XR8 help..

[Regan]

G’day,
I have an AU XLS V8 manual ute with 250,000km under its belt now - I’ve owned it for 6mths and its been a slow process tidying things up - first was a full service - all oils - fix
oil leaks from the gear box speedo sender - rear gear box seal - power steering leaks - diff leak that I ended replaced with a complete LSD XR6 BA swap out as the backlash and the whine coming out of the original diff one had to almost wear hearing protection it howled that loud - the a/c was a bugger to get going - that had to be out sourced to auto electricians to get to the multiple failed connections - new struts and brake pads - bump stops in the front - then the task of getting rid of the dipping idle - I scoured the forum and other sites looking for answers then started checking and cleaning components one at a time to find the cause of the idle dip/drop fluctuation - the induction had one of those wonder spray cleans befor I picked the ute up which I’m not a fan of - from the air box through to the intake plenum - I replaced the ICV as it looked old but unplugging it and plugging it back in suggested it was working - the bypass valve and ports had a lot of crud in them so I cleaned them and ran it like that for a few weeks before fitting a new ICV - no change to the idle - I then set the idle speed with the new ICV disconnect - I had to turn the throttle stop in near two and a half turns to achieve the desired idle then reconnected the ICV - with the idle set the fluctuation was still there but was better to drive stalling the engine less but you had to keep a light load on the throttle at low speed or it would jerk violently - so the MAF was cleaned next - it didn’t look to bad but had a little bit of crud around it - so I cleaned that gently as some stuff was stuck to the heater wires - it used to run an oil type K&N filter which may explain the stuff stuck on the filament - that made a little improvement with a steadier idle and less rpm dip but it still wasn’t sweet to drive as it would jerk at low speed if not keeping a light load on the throttle - next up was the air temp sensor - no difference - I should also mention I changed out the PCV as the original was worn and I thought I might be on a winner but no - I also looked for vacuum leaked but the dipping idle didn’t support a vacuum leak so today I removed the throttle body - it looked ok with a little carbon around where the butterfly rests at idle - I cleaned the bore and butterfly running super fine wet and dry around the butterfly edge and the bore and fitted it all back up - on first start the idle was at 1000rpm so I rest the idle and to around 600rpm - there was a noticeable difference straight away - I took it for a test drive and what a difference - crawl in first and no jerkiness with no load on the throttle - no idle dip or fluctuation - you can now creep up to a stop with no jerk or dip and a smooth idle - I should have tackled the throttle body first but was told it’s been cleaned by the magic dump of spray up it’s nostril - all I can say is the obvious is some times the obvious - it’s now sweet as to drive - best of all after a 3600km road trip towing a light 300 + kg load and fitted with a big *** canopy it averaged 8.5lt/100km - I’m so impressed - might not have the mojo of the bigger boss engines but it’s still a lovely little V8 that can growl when you need it to and hum a sweet exhaust note hour upon hour on the open road - now to sort out the cruise control