its starts fine but if i dont stay on the gas and rev it then the RPMs go low and low and then it dies. its a '90 with 4.2L and 2 barrel stock carb. what do i need to do?

Try cleaning the idle tubes in your carb, and your entire carb for that matter. Is your fuel filter clean? Does it die after it warms up, or does it die no matter what?

its fine when it just starts up but a minutes after i pull away and then come to a stop sign its dies. i just replaced the air filter and sprayed some carb cleaner into the carb and put some fuel additive into the gas tank

What brown said...idle tubes and fuel filter.. The air cleaner and fuel additives prolly did nothing for ya.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

ok thanks guys

Hoki What happens is the choke is engaged when it first starts and the mixture is enriched for a short while. Then as the KEY is on and electricity goes to the choke heater the choke slowly opens and the regular lean mixture comes into play. If the idle jets are clogged or the TUBES in the throttle body are stopped up... You get a little less to none at all gasoline in the engine at idle.
This small bit of gasoline is counted for when the hi-speed jets are installed...i.e. the engine COUNTS on the idle amount of gasoline at all speeds! So a carb in your (possibly) condition is running too lean at all speeds.
If that is the problem then it needs to be corrected.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

ok i pulled out the idle tubes and cleaned them out with wire and carb cleaner and put it all back together and it worked fine and didnt stall, idled very steady and right around 800 to 900 RMPs after i adjusted it. that was around 2 today and now its starting to idle very low again and sputter at stop signs but not stalling. what should i do now? change the fuel filter?