Car runs great when cold, idles perfect, plenty of power. Once the car has been running about 20-30 min it starts to act funny, studdering, missing, I can smell gas, backfires, and when I'm taking off from a start the engine feels like a machine gun!! Coming to a stop I have to keep giving it gas to keep it alive.
I replaced the o2 sensor and no luck.
Can anyone help me with this, I have no idea what's wrong with it!

 

The same thing happened to my grandpa's truck and it wound up being a sensor on the intake. It was a temperature sending unit of some kind. When the code was pulled it told you which sensor it was.

 

Car is not throwing codes, sel not on at all!
I replaced the ignition module and went through the vaccume system and everything appears to be working right.
I'm going to replace the fuel filter and if that doesn't work I'm just going to take it to someone.

 

1st place to start is check all your plug wires.
Ohm all your injectors (1st cold) then hot when its starting to break up.
Check Your Plugs how do they look? tan , whitish , black ?

Make sure the ignition module is in fact good. A buddy of mine went thru 8 or more from the parts store. Same thing when cold was fine. Soon as it got hot it would break up bad. Almost to the point of not driving.

 

Thanks for the advise
How can I check the resistance on the injectors?

 

Do you have a digital mulimeter?
Here a quick google search for it pops this up on youtube