What are the chances timing could jump on startup on a car that's sat for awhile through the cold weather? I fired up my SL today and it seems to fall on it's face at about 5psi boost (Autometer A/F guage goes straight lean when it does this). WOT seems to cure the lean condition, but it just doesn't pull (it will make it to 10-12psi, but takes a long time to get there). It ran normally when parked (other than axles clicking/popping). No codes other than 12 & 55 (battery was disconnected).
This is a Shelby Lancer, completely stock other than boost and A/F guages.