I don't have any mods on the engine. My question was about APV was about the valves. I noticed that the cable connected to the servomotor that was controlling the valve on the piston in question was way too loose. Would that have an affect on fuel/oil mixture? And what do you all mean by detonation?
Thanks for the input so far.
I was using BR9EYA plugs.
Typically I would say the APV cable isn't going to do crap with your air/fuel mixture. But on an efi I suppose your ECU could have you running lean just prior to it opening and with it not coming open you might have a bit of a lean spot. But again I doubt the APV cable had anything to do with it. Honestly I would bet money this isn't it. Look somewhere else for the problem.
Not your plugs running hot. BR9EYA's are pretty darn standard.
Again like others said. Long pull running lean burned it down. Melted the exhaust side of the piston off. Pretty simple. Rebuild it, jet up and run it.
As for detonation. If it is a bone stock sled then detonation isn't the problem. Detonation is really a factor when running a head, turbo, pipes that add running compression, etc. On a stock sled running 91 oct this isn't it.
What sled, what is your jetting, what were the conditions, Cold weather. etc.
They all play a part.
Good luck.
Thunder