Replaced a/c belt and alternator belt now it will not start

Replace belt tensioner, any other pullys, I worked on ? vehicle where the pully would spin but would stop every so often.

I am thinking faulty injectors and/or excessive fuel pressure in the fuel manifold . Run fault codes again ensuring that the cables used and the procedure to connect is adhered to as there will be a fault code recorded but not being read

Defective alternator , replace and check tensioner , and tensioning of belt .

One of the belts is loose. I would say it is the Alternator Belt.
What happens is that when you use the battery to start the car, the alternator immediately attempts to charge the battery back up once the car starts.
If the belt is loose, the belts slips some, making that horrible screech, until the battery is charged enough that the belt no longer slips, because the alternator no longer needs to make as much power, and the screech goes away.

Check to see that your alternator belt is the next one to replace, and tighten it up to specs.

you could have an alternator problem, I am wandering if the serptene belt is on properly or tight. if the belt is slipping and not turning the alternator pulley then it will not charge you battery and if you drive it the new battery will go dead and the alternator is not charging it so it will not start.
i would charge the battery and start the car and watch the belt and the alternator and see if the pulley is turning, they will also make a squelling sound if loose.
hope this helps

Replace battery .Start car warm to normal, check alternator by removing battery negitave cable, if the engine quits running replace alternator if it keeps running the alternator is fine. As far as the serpentine belt goes it will not prevent the car from starting.However if the belt looks like it needs to be replaced then it might be a good idea to do so.Good Luck.

The alternator drive belt is loose or worn out. If the alternator is driven off a serpentine belt then replace the belt. Inspect the serpentine belt tensioner and replace if necessary. On an 18 year old car it is more than likely defective. If it is driven off a standard drive belt then adjust the alternator to tighten the belt. Inspect the belt for fraying and or cracks and replace if you see any.

Unplug the connector on the back of the alternator, remove the bolts holding alternator to the mounting bracket.
replace the alternator, start in the bolts, and set the belt on. now use a small pry bar, to hold pressure against the alternator to tighten the belt. while holding belt tight, tighten down the mounting bolts. rehook connector on rear of alternator. if you feel safer, unhook the battery + terminal before you start the replacement.

Don't drive the car until you make sure the belt that is shredded is not the water pump belt. YOU could drive but the engine will overheat and have a more costly problem. Two things, if the lights are working but the car is not starting. It could be that the terminals are dirty on the battery AND if the belt that is shredded is the Alternator belt, the battery could be just down on charge. Do to things (1) Find out which belt needs to be replaced and have it replaced. (2) Charge the battery, maybe a friend has a charger, if so have them trickle charge the batter for at least 12 hrs. Less there's some other problem that should take care of it.

there's your problem......you have a cheap alternator. Buy atleast refurbished never used once especially from a junk yard. Sounds like the pulley is worn.