My check engine light is on could this have anything to do with my belt going bad on the car?

The flashing engine light means the miss is bad enough to cause damage to the catalytic converter. The check engine light does not involve engine oil.
Are you saying the timing belt is not turning the cam ?

Check belts for proper tension check output on alternator. When you turn on the a.c. it puts a drag on the engine which slows down the engine could be the alternator going bad try revving up the engine with the a.c. on to see if the light goes out. Listen for squealing belt indicating a bad belt tensioner or worn belt out of adjustment. Hope this helps also check for worn wires going to the compressor m as king sure there are no worn exposed wires grounding out on the engine or frame causing a short in the system. Hope this helps.

Check alternator output with voltmeter across battery. Battery alone, 12.5, but rev engine and must go over 13.5, or else bad alternator, loose belt, dirty battery terminals, bad engine ground, etc.

did you check the code?

Well it is an interference engine which means if the belt breaks the pistons could damage the valves.
If it only jumped a couple of teeth it may not have damaged anything.
I would put a new belt on and check compression.

Check the alternator pulley for a wobble when the engine is running. WIth the belt off pull up and
down on the pulley, check for up and down movement. If the belt popped off, you have some movement on one of the pulleys, a bad belt tensioner, or just the wrong belt. So check the belt tensioner as well. And find the part number on the new belt and check online to see if its the correct belt. But Im fairly certain its the alternator.

I think you have a bad bearing on your alternator. The bearing can become loose and reseat itself for a while, then loose again. Could explain the battery light randomly coming on.

Have the alternator bench tested at the auto parts store as well.

Did you check the serpentine belt to see if it was broken?

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how can it be dead and you not find anything bad??? take it back to whoever did the timing belt. something is BAD WRONG>

No repair should only last three weeks...don't touch anything and have the shop that did the work come and get it. I have lots of ideas but it will need to be checked over to verify them. Rather than comment on the "maybe" of this, have them check it out. Any reputable shop will be more than willing to do what's needed...Bad jobs ruin that reputation!

sorry I got a head of myself without a check engine light it probably isnt a mass air flow the 2.4 liter engine is a very very touchy engine I don't think that there would be anything covered by the waranty as its a 2003 things to check first would be tune up condition including a fuel filter and the most important thing is the timming belt and balaceshaft belt