Low and rough idle . sometimes stalls with ac on. worse when warm

Dirty air filter, dirty throttle body...try 2 bottles of gas line fuel injector cleaner...has your car been parked for awhile? Heet gas additive will work on any low gas tank sludge that you may have. Hope this helps.

If it's surging, make sure your radiator is full. Do a tune up, plugs, wires, etc. Put some fuel injector cleaner in your fuel tank. On a cold start the vehicle compensates for being cold by adding fuel. Once it warms up the computer tells it to quit adding extra fuel. If it is a bad sensor of sorts, check engine light should come on.

TRY REPLACING YOUR PCV VALVE

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spark plugs good

Check when idling and warmed up if the rev drops when the AC is on. It may be too low or is running rough. You may have to adjust the idle screw with little adjustments. If the idle is running rough, inspect the idle air control valve. It may be dirty or faulty.

SOUND IDLE AIR CONTROL VALVE NOT WORKING PROPERLY.IT SHOULD STEP UP IDLING WHEN YOU TURN ON THE AC TO KEEP ENGINE FROM STALLING OUT.

Everything you are describing leads me to believe the battery is the culprit.Not enough storage in it after it sets,when it does start the alternator has to work at max to recover from the start making it idle rough,and the fact that it starts good warm tells me that you definitely need a battery.You can confirm this by boosting the truck the next time it starts "just clicking",if it goes with a boost then you will know for sure that the battery is done in.

should idle around 700

put a throttle position sensor on the throttle boby this should fix the problem!