I need a diagram for installing a serpentine belt on a 94 buick skylark Or I need to know where the tensioner is located and once i release the tensioner will i be able to slip the belt around the pulley next to the altenator?

After you get your diagram at this website go over to auto zone and borrow the serpentine belt tool kit and it's very easy to change the belt.
Serpentine belt Serpentine Belt Diagrams

You shouldn't need to loosen the tensioner itself. To release pressure on the belt tensioner, rotate the belt (or tensioner pulley if the belt is no longer installed) CLOCKWISE. This will release the tension to either remove the old belt or install a new one. Once installed, the belt tensioner will automatically take up the slack.

look for small pulley with a square hole in it then you will have to install a 3/8 ratchet into it and pull in either direction until you see the belt loosen its a spring loaded tensioner so it will return once pressure is relieved, be careful these tensioners are very strong. in some cases they use a bolt and you will have to use a socket to release the tension most tensioners are located towards the center of the belt routing.

a tool may be needed to take tension off the tensioner, then take the belt off. before you do that, find the diagram of the belt routing or make you own little map.

Click on the following free direct Link. It has the Serpentine Belt Diagram and Tensioner location for your 2002 GMC Envoy. Plus Instructional and Directional Diagrams you will find very useful.

http://www.2carpros.com/car_repair_information/year/2002/make/gmc/model/envoy/2002_gmc_envoy_drive_belt_routing_diagram.htm

GENERAL/Standard Rules to Removal the Serpentine Belt with a Tensioner:
A. Find the Tensioner(s). (See Diagrams on Link)
B. Using a Serpentine Belt Tensioner Tool, Or Wrench OR Ratchet, Rotate/Move the Tensioner USING THE AVAILABLE NUT (on the Pulley or Arm Base) OR the OPENING (3/8ths or 1/2 inch square opening) rotating the Tensioner Pulley/Arm - moving it away from contact with the belt and towards the area where the belt is not in contact with the Tensioner Pulley. The Tensioner is spring loaded, and is hard to rotate/move.
C. Remove the loosened belt off one of the other more easily accessed Pulleys.
D. DO NOT quickly release the Tensioner, but gently allow the Tensioner to rest in its closed position.

Standard Rules for Installing the Serpentine Belt with Tensioners:
a. Pick a Pulley that is most easily accessed. This will usually be on top. This will be the last Pulley that the belt will go on.
b. Using the Diagram: Install the new Serpentine Belt on the remainder of the Pulleys....over, under, left right.
c. Using a Serpentine Belt Tensioner Tool or Wrench or Ratchet Tool: Rotate/Move the Tensioner Pulley/Arm "away" from Belt contact area on the Tensioner. This spring is pretty hard and with a new belt, it will be even harder to install. Rotate/Move this to as-close to the maximum allowed inorder to have enough slack in the belt to get it up and over the last pulley.
d. Using your other hand - Pull the Belt up and over the Last remaining Pulley.
e. Before releasing the pressure on the Tensioner, visually inspect the remainder Pulleys and the Belts' Positioning on them.

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.Com!

Click on the following free direct Link. It has the Serpentine Belt Diagram and Tensioner location for your 2003 Chevy Impala.

GENERAL/Standard Rules to Removal the Serpentine Belt with a Tensioner:
A. Find the Tensioner(s). (See Diagrams on Link)
B. Using a Serpentine Belt Tensioner Tool, Or Wrench OR Ratchet, Rotate/Move the Tensioner USING THE AVAILABLE NUT (on the Pulley or Arm Base) OR the OPENING (3/8ths or 1/2 inch square opening) rotating the Tensioner Pulley/Arm - moving it away from contact with the belt and towards the area where the belt is not in contact with the Tensioner Pulley. The Tensioner is spring loaded, and is hard to rotate/move.
C. Remove the loosened belt off one of the other more easily accessed Pulleys.
D. DO NOT quickly release the Tensioner, but gently allow the Tensioner to rest in its closed position.

Standard Rules for Installing the Serpentine Belt with Tensioners:
a. Pick a Pulley that is most easily accessed. This will usually be on top. This will be the last Pulley that the belt will go on.
b. Using the Diagram: Install the new Serpentine Belt on the remainder of the Pulleys....over, under, left right.
c. Using a Serpentine Belt Tensioner Tool or Wrench or Ratchet Tool: Rotate/Move the Tensioner Pulley/Arm "away" from Belt contact area on the Tensioner. This spring is pretty hard and with a new belt, it will be even harder to install. Rotate/Move this to as-close to the maximum allowed inorder to have enough slack in the belt to get it up and over the last pulley.
d. Using your other hand - Pull the Belt up and over the Last remaining Pulley.
e. Before releasing the pressure on the Tensioner, visually inspect the remainder Pulleys and the Belts' Positioning on them.

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.Com!

This SHOULD be how it's done, but not so on the 90's Park Aves.
With this 3.8 L V-6, you have to remove the motor mount on the side of the engine--and without the proper tools it's about a $290 job for the dealer.

check if it has a tensioner, it look like a useless pully and put a breaker bar on it and pull it and the belt should loosen up, if theres no tensioner the alternator should have bolts to loosen up the belts.

Your vehicle has an automatic belt tensioner. It should be located near the other pullies because the belt runs over it too. Usually required is a ratchet or box end wrench to work it. Once you get the wrench on the pulley, pull the tensioner loose to remove the belt and the reverse to replace it. The vehicle should have a routing diagram for the belt.
I believe the belt diagram is on the left corner on the passenger side.
Good luck and hope this helps

have you tried going through the fender well?