all the things KM says are good starting points.
a couple things to remember when starting cold engines... Lead acid batteries (even AGM) have less voltage and less capacity when cold.
add to that thicker oil (harder to move/pump/things just dont spin/slide easily) when cold means that the starter works harder to turn the engine over.. meaning it needs more voltage and current to work (which the battery is already short on due to temp).
soooo, anything you can do to make it easier to start will help. Now, to start in colder weather, you will need more fuel (choke), adequate cranking speed, and a hot spark.
will add in ign coil mod as one that will help with cold starts, as it allows the coils to get more voltage on the primary, which results in a higher secondary voltage (better spark).
make absolutely certain all your grounds are good (have seen grounds behave in warm weather, but go to shiat when the temp drops, then be better when the temp goes up a few degrees). Also, make sure the cables from battery to solenoid and solenoid to starter have good connections.
will add in here our 'choke' isnt a traditional choke you would find on a car, but actually an enrichment system that lets in more fuel AND more air as well (for a 'fast idle' type of affect). its possible that your enrichment system isnt allowing enough fuel in for the amount of additional air being let in.
Last edited by michiganteddybear; 11-20-2014 at 12:54 PM.