hrmm only thing I can think of is sh!t fuel..? is is a V8? the VE V8's are designed to run on 95 octaine fuel.. but will still run on 91 octaine (if it has to, decreased perormance - limp home) are you doing long distance driving.? it seems like you have pulled up at some Sh!t fuelo in the middle of no where and most probably picked up the premium pump and if anything got sh!t quallity, dirty or even expired 91 octaine fuel.. the same thing happened to my VE Clubby about 2 weeks ago.. I went to a shell fuel station in the place i live and paid for 98 octaine Optimax fuel and drove away. not before long i was having the exact same problems you discribed. engine pinging like fu*k, surging, misfireing the whole works... not to help any my engine has been tuned to run only on 98 octaine, also my air intake is maffless! I went back and complained to them but they pretty much told me to Fu*k off blaming the problem on my car coz it has been modified and not still factory. So i then went to fuel watch and complained to them, they asked me for a copy of my reciept and a sample of my fuel to be analized. I had to take my car to some fuel analizing depo for them to take the sample so i couldnt "tamper" with it. I done that and a few days later gave me the results! Pretty much I had paid $132.11 for 73 litres of 91 octaine unleaded that was made up of about 16% water! so actually i paid for and pumped 62 litres of 91 octaine unleaded and 11 litres of water out of a 98 pump at 98 octaine fuel prices! into my tank. now that fuel station is in the sh!t and I might be compensated for the damage done to my engine (if any has occured) and the investigation is still on going now! Fu*king arseholes
also just to let you know while i was having these problems my car did not show up any warnings or let me know there was a fault.. tech 2 might be able to get something tho, wen it gets its servive on monday