Hard cold start , coolant temp replaced , start injecter rigged with remote switch , it still floodes out

Bad coolant temp sensor--makes ECU think engine is still cold so sends too long injector pulse flooding engine. Very common, and easy fix.

When a temp sensor goes bad, it usually fails to a setting that makes the ECM think the coolant temperature is about -40 degrees F. This makes the ECM send MASSIVE amounts of fuel to the injector(s) in what it thinks is an extremely cold start. This causes the engine to flood and makes for a hard start. You may be able to get the car started if you do a "Clear Flood" procedure, which is to hold the gas pedal to the floor while cranking until the car starts. Even then, though, the car will run so rich that you may have to keep revving the engine to keep it from stalling out at idle. On the road, it may seem better, but your fuel mileage will be awful.

On thermostat housing there are three compmnents. One has a yellow wire going to it. That is the coolant temperature sending unit for the temperature guage. The second unit above it is a coolant temperature sensor which relates to the fuel injection system to tell the compueter what temperature the coolant is. The third switch is the thermal time switch and is the largest of all of the switches in the housing. This feeds information to operate the cold start injector which is operated for a "very" brief period of time (or window in which the circuit to the cold start valve wil energize) and is not quite the same as a choke. Just because the engine is cold doesn't guarantee that the cold start valve is going to energize. The sensor is more like a buackup to keep the cold start valve from opening every time you turn the key. The engine temperature just insures that this will not cause an accidental occurance flooding condition. It will not operate even it you have let your car sit for hours after having driven it. Usually it takes all day unless in a very cold climate, or over night before it will operate again. The coolant has to be stone cold.

try to give it a little more gas it sputters an back fires! In the first place your not giving it more gas unless it running ! If just cranking all your doing is letting more air in . Your vehicle has electronic fuel injection , not a carbuerator . Till the computer see's a RPM over 300 rpm , it's going by programming installed in the PCM - engine computer . It sputters an back fires because of a lean condition , low fuel . When starting a fuel injection engine you don't touch the throttle pedal . And if you were to push it to the floor and hold it , the computer goes into clear flood mode. If the vehicle were flooded that is what you would want to do .
P0320 OBD II Trouble Code
You may have O2 sensor problem or a map sensor or coolant temp . sensor . Your best take it an have a qualifiedd repair shop diagnose it .

Do you have a scan tool ?
049 Engine Hard to Start or No Start Scan Data for Vacuum Leak
048 Engine Hard to Start or No Start Scan Data for Starting Problems
047 Engine Hard to Start or No Start Scan Data for Ignition

I'm assuming the engine cranks with the starter but does not start and run.

check the operation of the cold start injector. This is a separate fuel injector that injects fuel into the intake manifold to help richen up the mixture for cold starts. It operates on a timer that is linked to a sensor that measures engine coolant temperature. Once warm or the timer runs out, the cold start injector is turned off. Other things to check:

Fuel pressure too high (floods engine through cold start injector), engine coolant temp sensor or intake air temp sensor is stuck at full hot (doesn't allow enough fuel for cold starts), fuel injectors are leaking (floods engine with fuel).

If the connector to the coolant temperature sensor is loose, that could be causing the problem since that controls certain functions of the computer when the vehicle is warm vs. cold.

It is your engine coolant temp sensor (ECTS). 99.9%. the saturn made them with a plastic tip, so they crack over time. A replacement should be about 15 bucks and not too hard to replace. You'll notice your engine temp gauge not working (always cold).

I don't know much about cars, but here's what happens. When your car is cold, the fuel runs rich. Your broken sensor is always reading that the engine is cold, but when it is warm, it runs too rich and floods your engine, not allowing it to start. When your engine is actually cold, everything is fine.

they rigged the fan directly because the temp sensor is defective. nothing wrong. just don't forget to turn on always the fan switch. or if you want, replace the temp sensor.

check fuel pump and filter