My 1999 Civic, manual trans, 127k, 1.6 4 cyl, has problems starting if the car has been sitting for more than 1 hour. For example, if I go to store for 5 min and start the car, it starts up instantly. Car drives fine and when I “Floor it” Peddle to the floor, i have all the power there. Its just when i start the car after 1 hour of sitting, or over night, it takes a good 5-10 seconds of cranking to start.
The check valve is in the fuel pump. This is what maintains fuel pressure when the car is not in use.
Offhand, it sounds like the pressure is bleeding off slowly and the cure is a new pump. This can be verified with a fuel pressure test.
While not likely related, I think your particular model of Civic is under a Recall for faulty ignition switches which can cause a no-start or random stalling situation. This is probably not the cause of the current problem but seeing as how it’s a free of charge fix you might consider having that done by the local Honda dealer.
To add some background info to the good ideas in the posts above, the fuel injection system requires an input of fuel under high pressure to function properly. If it had to pump up the fuel in the tank every time the car was started, this would be the symptom as it takes some time to reach the needed pressure level, just like it takes time to pump up a bicycle tire with a bike pump. So it has a gadget called a “fuel rail” which stores a small quantity of fuel under a fairly high pressure, even when the engine is turned off. Then every time you are ready to start the car, it has enough fuel already under pressure available to start right up.
What appears to be happening is your fuel rail pressure is leaking down. This can be confirmed by a fuel pressure test. You don’t see any visible gasoline leaks b/c the leak is internal to the system. It is either leaking from the fuel rail back into the gas tank via the fuel pump check valve, or an injector is leaking gasoline into one of the cylinders. Usually it is the former, and the fix is to replace the fuel pump.
What i have found is that when i turn the key to on and back to off about two times to pressurize the system, that the car will start up very quickly. So i think it is the pump. I am going to replace it, pretty soon. Thank you all for your help on this one. I really appreciate it