99 sunfire starting problems

I;m having problems with this car. If you just turn key to start it will crank fine but wont start. Pressing throttle to the floor it will start. It also has a stumble from dead idle but runs great past there. And drives great on the road. Any ideas on this problem? Or could it be the throttle positioning sensor?

simple one this. Throttle body needs a clean IAC valve is full of gunk.

I removed, tested and cleaned the IAC and still does the same thing. I ran a computer code test and it keeps popping up a P0118 fault code. Engine coolant high input.is the sensor bad or does something else send that sensor a signal thats too high. Thanks for any help or suggestions.

check for spark at all of your cylinders. if no spark, check electrical connections to the ignition control module. if there is spark, i'd suggest changing out your fuel filter if you haven't done so in awhile.