Here's the situation:
I have Cobb and PTF protune running 20% ethanol/93 octane (3 gallons E85 in a tank with balance 93 Shell). BMS DCI and Helix FMIC. No DPs.
35,000 miles on original coils.
Changed plugs 4000 miles ago.
All of my cylinders are quiet with essentailly no timing corrections. But once the oil temps reach about 230F, cylinder 1 timing shows corrections up to -9 degrees in stop and go, daily driving. Air temp 68F. All the other cylinders are quiet, perhaps only -3 deg timing corrections here and there in DD (AFR about 14 or 15).
Note: I don't see any timing drops in any cylinders during WOT pulls (AFR -> 12).
Question: why is only cylinder 1 showing the -9 degree timing corrections in DD driving, but not WOT?
I'm thinking that as the plugs are pretty new, but the coils are original, it may be coil #1.
Your thoughts?
