I've done a search on pinging topics and I've gotten some info back, though no one's problem seems to be exactly the same as what I've got here....
Well i'm fairly sure I've got a bad batch of fuel (Very bad batch)
I filled up with BP Ultimate (Use nothing else) on Wednesday arvo, and on Friday morning as I left home for work the engine started pinging it's tits off. This is after about 100km of driving since filling up. I managed to get myself to work with some careful driving to avoid it pinging, though I noticed that once the car was at full operating temperature the pinging stopped completely and I could drive it normally.
Though in the afternoon driving home (still very carefully) It didn't ping at all until it got to full operating temperature, and not as much as before.
I spent the whole afternoon trying to sort it out, it's got a new fuel filter and a bottle of octane booster in it, the tank is about 2/3 full now.
Now it will still ping, about as much as it did yesterday. Doesn't seem as though the octane booster has made much of a difference. (Although I've only driven about 5-10 "testing" kms since it was put in, I guess that's probably too early for it to take effect. I've never had to use booster before so I don't know how long it takes)
When idling it purrs like it always does, the car drives dead smooth, I don't know if it's losing power as I'm certainly not game to give it a boot. It's not misfiring/running on 4/5 cylinders.
It seems to be most suseptible to pinging if I'm only applying the lightest amount of throttle (5-10% let's say). That being said, I haven't given it anymore go once it starts, I just back off straight away.
It doesn't need any boost or hard driving to start pinging.
Any ideas? I'm not really in the mood for buying another neo.....
Drain fuel tank?
Could this be the result of fuel companies toying with ethanol mixtures as mentioned in the news?