Wont take throttle in first gear?and pops at an idle.

Do the throttle body cleaning and re- learn idle speed control valve.

If you know for a fact you have no vac leaks, the next step would be to check the idle air control valve. It should be mounted in the throttle body. It could be stuck open.
The computer controls idle speed by regulating air flow into the throttle body.
The throttle plate could also be stuck open. An eighth of an inch would do it. Make sure the throttle and cruise control cables are not pulling on the throttle plate.
Vac leaks could include the PCV valve and the EGR valve.

Sounds like a throttle position sensor. It should be on the throttle body itself.

u need to take and remove the air induction tubing and clean the throttle and butterfly w/ a toothbrush and throttle body cleaner do not use carb cleaner this will ruin sensors

have you checked the EGR (exhaist gas recirculation) valve? sometimes carbon will chip off and make them stick partially open causing extremely rough idle or wont idle at all without help from throttle

hold revs up for approx 5-10 seconds then slowly bring back to idle if it still stalls have to adjust air bleed screw in throttle body to adjust idle speed
ECU needs to relearn must put in gear then turn on a/c while in gear idling and then turn on head lights then put in neutral while other things are on then turn off all things and go for drive

sounds like it has a vacum line loose try to find the hissing and check all the vacum lines around that area

put the crank at TDC and the cam gear and TDC slip the belt on adjust the tensioner and then rotate the engine two times make sure the timing marks are still lined up then put it back together and try it if you have the timing off it wont idle right and if could also be the throttle positioning sensor

check that routing of your throttle cable going to the top of the engine, sounds like it may be dry (no lube) or kinked somewhere. also check for a bent bracket where it would go through.

u may need to have ur idlein ajusted to specs