It takes a good 4-5 secs to start some times while other it’s instant. My gas mileage is horrible... I have changed fuel injectors, spark plugs, coil packs. Have also been putting seafoam into it. Also a very strong gas smell is coming from my exhaust. I don’t really know what else there is to fix this problem that has been ongoing for 3 weeks now...
It sounds like your engine is getting an alternate source of fuel somewhere, too much fuel pressure, or a mis-reporting sensor such as the coolant temperature, or mass air flow.
As @moab has kindly pointed out, your vehicle does not have a fuel pressure regulator on the injector rail as the slightly older models did, so that can be eliminated as suspect in your case.
A fuel pressure/leak down test should be performed, as well as a system scan of all sensor values, and modules for any other manufacturer specific module codes that might not show up on a generic OBDII scan. These tests should shed some light on where to look next.
your description sounds like o2 sensors..un plug positive battery cable replace both o2 sensors let set for about 30 minutes reconnect battery cable start engine..when replacing the o2 sensors use a good brand like bosch