Follow up!
Over the Xmas break I was lucky enough to have this car delivered to me on a tow truck in an obvious sick state of health and was able to begin full diagnostic attack of this issue.
The car had some prior history of very poor repair methods which included an engine change as well as just general shit workmanship, in short they contributed to the fault.
Visual inspection initially picked up on boost/vac leaks from incorrectly fitted hoses,clamps,pcv and stripped bolts almost holding on bpv as well as the wiring being incorrectly routed and all 3 earth tails but floating in the breeze!
A DTC check after clearing all history revealed cylinder x misfire which gave me a starting point for trouble shooting. In addition to checking the dtc with ap I was able to monitor pcm inputs and noticed that the fuel trims and afr where showing up as perfect which it was clearly running super rich!
I proceeded to fix everything I could see was wrong and returned the car back to how it should be ( this step makes it hard to positively find the cause of the fault but catch 22) Much to my surprise absolutely nothing improved and I still had a sick car on my hands.
From this point I followed the trouble shooting fault tree for cylinder X misfires ( read to shop manual if your interested)
during the fault finding process many of the tests were inconclusive and any doubtful results were inconsistent when compaired to known good vehicles.
I was confident that I had correctly diagnosed a faulty pcm but I wasn't going to buy a $2000 PCM without being 100% sure! Lucky for me I have a good support network and Troy was kind enough to send me a full cars worth of modules! Unfortunately this option didn't work as planned and I needed an alternative to confirm my diagnosis. Thankfully I have built a good relationship with some fairies who were able to program the borrowed system and ultimately confirm my diagnosis of a fried pcm!
The instant the car started it ran like garbage due to the large un calibrated maf however I now was able to monitor stft's outside of thresholds, I also tricked the maf and was able to free rev the car misfire free.
An unfortunate situation for joe as he hasn't been able to enjoy this car, so hopefully with the time spent and all underlying faults repaired he may enjoy his ride into the future!
Make sure that repairs are completed correctly or you will have a ticking time bomb.
Every man should have a V8 ute.....with a Chev badge.....and a Southern Cross sticker! Mods? What mods?