No check engine light but i get a backfire when i give it gas not as much when i accelerate slowly i checked wires,spark plugs,coils everything seems ok i think it could be bad gas or converters any comments will help thanks

 

Maybe you need new o2 sensors. how miles is on the car?

 

the problem got worse white smoke out of the exhaust it was the intake manifold gasket

 

you're running way too rich,this basically means that there is too much fuel going into the combustion chamber and not all of it is being burnt. a bad oxygen sensor will give you a check engine light which you havent gotten so i doubt its the O2 sensors. check your air/fuel mixture that should tell you a lot. there are many factors that can lead to running rich: timing, ignition system, the infamous leaky injectors,huge vacume leak, etc.

what kind of engine do you have? what mods? what year? milage? have you messed with the injectors? have anybody messed with the ECU? all this should be taken into consideration. let us know so we can try to narrow it down

NOTE: just noticed your last post. yeah a bad intake manifold gasket will do that because of the huge vacume leak it will cause. In most cars the ECU will detect more air in the system and it will automatically assume that you are opening up the throttle and will throw in more fuel thus making you run rich.

yet i'm still concerned about the white smoke, usually when you run rich the smoke is always black like diesel trucks, white usually means that you are burning coolant (blown head gasket, maybe)

how does the smoke smell???