My car runs fine, but has trouble starting when engine is cold.

Check the spark plug wires. See if they have any cracks or wear. Warmth keeps them dry, cold they get a little moisture on them.

This could also be an indicator of a bad spot on the starter even though you have had it checked.

My guess is that is a fuel issue. When you let a car sit long enough for the engine to get stone cold, some cars lose fuel pressure and take a few seconds to start. I had a Subaru that sometimes did that, and I got into the habit of letting the key rest in the ON position for about three seconds before cranking it; that was long enough for the fuel pump to pressure the system and it fired right up. Not doing that either made it take longer to start or stall after two seconds.

@jerv‘s answer is spot on. It sounds like a fuel issue. Weather it be the same problem he described or another, but it sounds like I’d pay attention to the fuel system. When you turn the key to the on position (before turning over the engine) do you hear a little hiss? That’s the sound the fuel pump makes when it’s priming the system, as @jerv mentioned above. Also I might ask when the last time your fuel filter was changed or if your PCV valve has ever been replaced. Also, fuel system cleansing might be a good thing to try.

I would make sure your battery has enough cold cranking amps for the climate you are in. I would also check the choke setting on the throttle body, some cars have a choke that stays closed until the engine gets warm enough at reg. operating temperature. If it has any of that wild stuff Like a MAP or MAS sensor it could be any of those causing it not to start right away.

Also, might sound crazy, but a loose ground could cause these types of problems. AND, sometimes when poeple work on the battery and starter, they make the common mistake of forgetting to reconnect the ground to the frame. If the battery is not grounded to the frame, the car WILL run, but will have issues starting and tends to cause some lights to come on even though those are not real problems. (Such as air bag light, and gas light with full tank, etc.) Plus, if you have electric locks and windows, they may have some glitches.

Mostly starting problems relate to a choked carburetor in cars. If engine spark plugs are not dirty or damaged, then the choke needs to be repaired or adjusted. In addition, a fuel injector or weak battery may be reason of such an engine-starting problem. An increase in viscosity of engine oil in the cold also causes slow cranking that leads to taking time to start (or warm up) engine. Using lighter viscosity oil such as 10W-30 is a better method to solve this problem. Check out more about engine problems and their solutions which I found at – www.hiperformer.com/engine_basics.