Tentioner pully bolt came out if that is what it is called. Do you know the size and thread of the bolt?

Losen the nut on the tentioner pully first then loosen the bolt on the tentioner and it will take tention off your belt . to put back on reverse this process

The belt tentioner pully is the idler pully in the serpentine belt system...
You need a long wrnch (11/16??) to fit the pullys center bolt...
Turn the bolt to the right ( righty tighty) and the tentioner will losten its tention on the belt enough to remove the belt...
Imediately replace the belt ... so its routing is not forgotten by time or distraction...
If there is still a sticker on the upper radiator support reflecting the serpintine belt routing.. then you are in a better spot to be doing this ... with distractions...

Most likely, tensioner is worn out and needs to be replaced.

I believe one bolt through the center of it holds it to the motor. Be aware that this bolt may have left handed threads so it would have to be turned clockwise to loosen if this is the case.

Remove belt, remove tentioner ,remove bolt holding pully on,replace pully and bearing,put tentioner back on, put belt back on.

a tensioner pully puts tention on your serpintine belt the bolt size verrys from vehicle to vehicle

there should be a tention pully that is spring loaded and you will need a socket to fit the bolt in the center. then turn clock wise and hold to release tention and set belt in place then slowly release the pully

there should by a small pully (called a tentioner) under the alternator pully, get a wrench that fits the nut in the middle and turn it counter clockwise this will loosen the belt to get it around the other pully. Ps. this is easier with two people, one to release tention and one to put the belt on.

TIMING BELT
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TIMING BELT
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DISASSEMBLY 1. Lift the vehicle by using of jack.
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2. Remove the engine support bracket. (14 mm bolt and 2 nuts, 17 mm bolt) 3. Remove the power steering belt. 4. Remove the air conditioning compressor belt.
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5. Remove the alternator belt.
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6. Remove the coolant pump pulley.
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7. Remove the crankshaft pulley.
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8. Remove the timing belt cover.
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9. Move the timing belt tensioner pulley toward the coolant pump and temporarily secure it.
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10. Remove the timing belt.NOTE: If the timing belt is reused, mark with an arrow to indicate direction of rotation (on the front of the engine) to make sure that the belt is reinstalled in the same direction as before. 11. Remove the camshaft from the camshaft sprocket. 12. Remove the crankshaft sprocket and flange. 13. Remove the timing belt idler.
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14. Remove the timing belt tensioner.


INSPECTION SPROCKETS TENSIONER PULLEY, AND IDLER PULLEY 1. Check the camshaft sprocket, crankshaft sprocket, tensioner pulley, and idler pulley for abnormal wear, cracks, or damage. Replace as necessary. 2. Inspect the tensioner pulley and the idler pulley for easy and smooth rotation and check for play or noise. Replace as necessary.
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3. Replace the pulley if there is a grease leak from its bearing.INSPECTION TIMING BELT 1. Check the belt for oil or dust deposits. Replace, if necessary.
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2. Small deposits should be wiped away with a dry cloth or paper. Do not clean with solvent.
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3. When the engine is overhauled or belt tension adjusted, check the belt carefully. If any of the following flaws are evident, replace the belt with a new one.
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REASSEMBLY 1. Install the flange and crankshaft sprocket as shown. Pay close attention to their mounting directions. 2. Install the camshaft sprocket and tighten the bolt to the specified torque. Tightening torque Camshaft sprocket bolt:.....80 - 100 Nm (800 - 1000 kg-cm, 59 -74 ft. lbs.) 3. Install the idler and tighten the idler bolt to the specified torque. Tightening torque Idler bolt: .....43 - 55 Nm (430 - 550 kg-cm, 32 - 41 ft. lbs.)
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4. Align the timing marks of the camshaft sprocket (A) and camshaft bearing cap (B). Then align the timing marks of crankshaft sprocket and front case with the No. 1 piston placed at top dead center on its compression stroke as shoved in the illustration.
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5. To install the timing belt tensioner, first mount the tensioner, spring, and spacer. Temporarily tighten the bolts. Next, temporarily tighten the tensioner long hole side washer and bolts. Install the bottom end of the spring against the front case as shown in the illustration.
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6. Secure the tensioner, positioned towards the water pump.
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7. Install the timing belt on the crankshaft sprocket. (1) Crankshaft sprocket - (2) Timing belt idler - (3) Camshaft sprocket - (4) Timing belt 8. Install the timing belt on the camshaft sprocket. When the timing belt is installed on the camshaft sprocket, make sure that the tension side is tight. Then, check to ensure that when the tension side is tightened by turning the camshaft sprocket in a reverse direction and all timing marks are in line. 9. Tighten the tensioner bolts. Tightening torque Tensioner attaching bolt: .....20 - 27 Nm (200 - 270 kg-cm, 15 - 20 ft. lbs.) 10. Turn the crankshaft two turns in its operating direction (clock-wise) and realign the camshaft sprocket timing mark with the top dead center position.
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11. Then recheck the belt tension Verify that when the tensioner and the tension side of the timing belt are pushed in horizontally with a moderate force approximately 49N (11 lb)], the timing belt cog end is approximately 1/2 of the tensioner mooting bolt head radius (across flats) away from the bolt head center.
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12. Install the timing belt cover. Tightening torque Timing belt cover bolt: .....8 -10 Nm (80 - 100 kg-cm, 6 - 7 ft. lbs.) 13. Install the crankshaft pulley. Make sure that the crankshaft sprocket pin fits the small hole in the pulley. Tightening torque Crankshaft pulley bolt: ......140 - 150 Nm (1400 -1500 kg-cm, 103 - 111 ft. lbs.)
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14. Install the water pump pulley. 15. Install the alternator belt and adjust the belt tension. 16. Install the air conditioning compressor belt and adjust the belt tension. 17. Install the power steering belt and adjust the belt tension.

I would buy the set so you make sure you get the right size. Use them and clean them up and return them and say they wouldnt work and get your money back.

You will need to buy a product called lok tight.Put some on each bolts thread before screwing them back in.Its a thread locking compound that works very effectively.Are the bolts too short?