Serpentine belt diagram for 1999 Chevy 350 5.7 engine

you did not specify what engine.
google 2009 chevy impala serpentine belt Diagram


copy and paste

https://www.justanswer.com/chevy/3ruw6-need-serpentine-belt-diagram-2006-chevy-3-5-lt.html

https://www.fixya.com/cars/t15630016-diagram_serpentine_belt_2009_impala_3_5l

It is possible to upgrade a 1987 Chevy 350 engine to a serpentine belt assembly using parts from a 1994 Chevy small block engine. However, there are some differences between the two engines that may affect compatibility.
One major difference between the two engines is the placement of the alternator. On the 1987 engine, the alternator is typically mounted on the driver's side of the engine. On the 1994 engine, the alternator is typically mounted on the passenger's side of the engine. This means that the brackets and pulleys for the serpentine belt assembly may be different between the two engines.
Another factor to consider is the number of pulleys on the serpentine belt assembly. Some 1994 small block engines were equipped with additional accessories, such as air conditioning or power steering, that require extra pulleys. If your 1987 engine does not have these accessories, you may need to modify the serpentine belt assembly to remove the extra pulleys.
To ensure that the serpentine belt assembly from the 1994 engine will fit your 1987 engine, it is recommended that you compare the parts and brackets from both engines side by side to identify any differences.

Pictures in the images tab and also videos

https://www.google.com/search?q=chevy+350+geneva+serpentine+belt+diagram

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T_330_81_1981_Chevrolet_Light_Duty_Truck_10_to_30_Service_Manual
http://www.73-87chevytrucks.com/techinfo/7387CKMans//Service/ST_330_81_1981_Chevrolet_Light_Duty_Truck_10_to_30_Service_Manual.pdf

GMC Workshop Manuals

There are 2 possible diagrams for your car depending on which engine it has. Both diagrams are listed below:


1999 Chevy Malibu 2.4L






1999 Chevy Malibu 3.1L

I have a 1998 K2500 w/ a 5.7 (350 cid) Vortec. I hope you find this useful.-JW

how do you route a serpentine belt for a 1988 chevrolet 350 ci with a ac. and airpump 2500 series truck

Serpentine belts are easy to change. The key is knowing where the 1/2" square drive tensioner is and to remove tension to the belt at this point.

If you remove the belt, it's easy to put the new one on because the pulleys are designed with grooves for the groove side of the belt, and smooth pulleys for the smooth back of the belt to ride on the pulleys.

Just go over, under, over, under until the belt is threaded on, except for the last idler pulley which is smooth.

Use the 1/2" breaker bar to turn the pulley until one can slip the belt onto the last 'idler' pulley and you're done.

First, keep this diagram around as you will need it to route the serpentine belt when you reinstall it. There may also be a diagram under the hood by the radiator.
Next, follow this link and watch the video that shows you how to replace a serpentine belt...
http://www.wonderhowto.com/how-to/video/how-to-inspect-and-replace-your-car-s-serpentine-belt-267229/