prolonged cranking when starting the engine only during the first start on 2003 Honda CR-V

the mileage of my crv is 47T, my spark plugs are about 5 months old my battery is new ,fuel filter and air filter are almost new,what could be the reason why i have to experience every morning when the engine is still cold,a prolonged cranking before it starts. It surely will start,only with a longer cranking unlike before when the cranking was short. Take note that the engine NEVER FAIL TO START in every attempts to make it start. The question is THE PROLONGED ENGINE CRANKING BEFORE STARTING. Could the problem be with the STARTER and if so,which of it's parts could possibly be worn out and needs replacement? An auto mechanic told me that it could be that the grease inside the starter becomes thicker when thge engine is cold or that the carbon inside might be short or thin already. I could not totally believe his theory since there is not much grease inside the starter that can become thicker to make it difficult for the armature to turn and start the engine. And if it is due to worn out carbon,then i should be experiencing this prolonged cranking all the time and not only during my first attempt when the engine is still cold in the morning. Thank you and more power!

Asked by for the 2003 Honda CR-V
You state that the engine cranks for a prolonged period of time, but you didn't say it cranked slow. If it cranks slow then it's possible that it could be the starter, but I would want to know what the battery voltage was and if the battery was drained overnight. If the engine cranks at the same speed as it always has then I would most likely be looking at a fuel pressure issue. I would hook up a fuel pressure gauge the night before to see if the fuel pressure drops overnight. Then I would check to see if the fuel pressure jumps up when the key is turned on when cold or if it takes some time to get to the correct pressure. The other issue that could be occurring is an immobilizer malfunction. Check to see if the green key light is flashing while the car is cranking. It's possible that the system is acting up when cold and takes some time to read the key.