Has the intake been off recently, or at all? I can believe it if not, they're notorious for the exhaust crossovers plugging up solid with carbon, choke operation is slow to won't
fully open in cold weather,...slow to won't come off fast idle,.....and Yes,... hesitation because the cold intake manny is lean now. I've fixed well over a dozen of those for
exactly that issue, the extra water temp may have been just enough to mask it at this stage if that's the case..............