I dont know which is the tension pully to get the belt off and how do i do it

on these newer cars with one belt they have spring loaded tensioner. looks like idler pully but pivots to tighten belt they are good for spring inside going bad. usually held in with on bolt next to pully.

regardless of the v6 engine u have the belt tenioners r phenominal about going bad in mostly 2 ways one way is not retracting or bouncing back and second is they dont stay aligned when it is pulled down from excellerating and it throws the belt.

Below the altenator is a tensioning pully, insert a 3/8" ratchet or breaker bar in the square hole on the tensioner and release the tension on the surpentine belt and remove the belt. Route the new surpentine belt in place up to the altenator and take the tension off the tensioner and put the belt over the altenator pully. Double check to make sure the belt is riding correctly on all the pullies before starting. Crank the engine over several times before starting to seat the belt.

the tensioner pully is spring loaded an d adjusts itself

One way you can usually tell is that the tensioner base mounts to engine with a bolt in the center of the casting, & pulley is offset from that casting. Put your wrench on the offset pulley bolt to relieve tension. There are various set-ups on that engine so maybe we better confirm which engine it is ?

u dont loosen pully there is a place on belt tensioner you put breaker bar, ratchet,or belt tool in to pull tensioner back to remove belt

this is the best guide/instructions I could find on the net and I do allot of this.
take the timing cover off the belt there should be a gear below the camshaft pully its a tensioner use a peice of chalk and mark the very top of the cam pully and the very bottom of the crank pully do your best not to turn them loosen the tensioner pully the belt will loosen up take it off put the new one on if you turned the pully put it back slowly tighten the belt when its tight if the pully turned when tightening pull the slack out by hand then tighten it both chalk marks should be lined up if they are start the car always unplug the battery first and dont rotate the pullys more than a few inches if nessacery when the belt is off you could cause damage to the valves

hi there .there r two belts inner belt goes throw the crank pully ,through tensioner and the alternator .the outer belt belt goes through the crank pully agine to tensioner and the power steering pump .sorry i dont have diagram but thats the way it goes hope it helps do send me the rating thanks

this is hard to exsplain without showing you a photo ,but i will try. first get the belt around the engine crankshaft which is the pully closest to the bottom and center of the engine. when standing in front of engine start to lead the belt to the right and connect to power steering pump then up to generator, next thare is going to be a smooth pully not groved like the others to the left,put the smooth side of the belt on bottom of this pully and continue left to the ac/compressor go around ac/compressor andstraight down to the belt tensioner , and then right over to the water pump which has a smooth pully not grooved. remember the smooth pullys will always carry the smooth side of the belt and the grooved pullys the grooved side of belt. the belt tensioner will half to be released by a serpantine belt tensioner tool sold at your local auto parts store. these instructions is for 3.8 liter engine, if you have a 4.6 liter engine it will be different, so repost stating that you have a 4.6 if this dont help

Timing belt or drive belts??