Hi James. It's a tricky one alright...so I'll just give my 2 cents
I have a 2003 ba falcon ute.
My problem is when the car is warm and has been left for about 15min (like going into the shop) when i go to start the car again it cranks over for a couple seconds and wont start try again and after another couple seconds it will start.
However in the morning or when the engine is cold it will start perfect hardley cranks over and starts and runs fine. the problem is only when it is warm.
There is a known heat-sink issue with BA PCMs, failing to start when hot only, lots of cranking but nothing else until they cool down a bit, but that doesn't seem to be your case. If you want to be 100% sure, take a bottle of cold water with you and pour it over the PCM when the problem is happening to see if it makes a difference, but i don't think it will
when i put my foot flat to the floor it will start alot quicker or even straight away. and if i turn the car off and turn it back on within a few seconds it will start fine, it only happens when it is hot and been sitting for a period of time. other then that the car runs perfect no other engine problems just starting.
When you put your foot flat to the floor you are effectively cutting off injection completely. If this makes it easier to start the car, it suggests your car is over-fuelling. You could be looking at a leaking injector or excessive fuel pressure (blocked filter or regulator?), or even a faulty CHT (coolant temp) sensor as someone suggested, but this should give a definite fault code when scanned.
the mechanic has no idea and just keeps on charging me money for doing nothing
Yeah we do that all the time
One last thing. If the Throttle body was cleaned you SHOULD disconnect the battery for a couple of minutes to reset the KAM learned values & allow the car to re-learn new ones, preferably when it's at normal operating temp.