2002 chevy suburban shuts off while driving

As of yesterday evening my 2002 Chevrolet Suburban 1500, shuts off while im driving. Takes about two to five minutes to get it going again (has shut off a couple times):uhoh: Starts up fine idles great, problems start about a mile or two of being drivien. Any help would be great!! Being that i just wasted $200 on a alternator just to find out thats not the problem.... Also REDUCED ENGINE POWER light came on??

Thanks

As of yesterday evening my 2002 Chevrolet Suburban 1500, shuts off while im driving. Takes about two to five minutes to get it going again (has shut off a couple times):uhoh: Starts up fine idles great, problems start about a mile or two of being drivien. Any help would be great!! Being that i just wasted $200 on a alternator just to find out thats not the problem.... Also REDUCED ENGINE POWER light came on??

Thanks
Why was alternator replaced?
What engine and milege?
Any engine codes?
You need to check fuel pressure when it starts acting up?
Have you checked fuel filter?
Does it have good spark when it quites?